He'd read somewhere about how at the start of Autumn the sea, having lapped idly on the pebbled strand for the previous six months, had begun to gnaw at it. No-one he knew had ever uttered the word 'strand'. But 'gnawing' was perfect. It always helped if the world could be made human: the ocean made angry and eroding, the sun unforgiving.

It was a bright day, blinding even, but what in the previous month might still have been a breeze was now a cold wind whipping off the channel. The woman in Reception told him he could turn the radiators up and he had; for ten minutes they'd been tinkling into life, like Morse from a captive in the adjoining room.

He lay on the bed, daydreaming to the distant splash of the tide. He'd left the car after he'd dropped Cath off at her Friday morning job and driven back home, just a few miles inland. He'd texted her that it wouldn't start. He'd walked into town, and caught a taxi. Cath might have needed the car; they'd need it: she and 'the little one', as his grandfather would have called Maddie. Friday night: they'd miss him at The Coastguard, where he was one of the 'regular regulars'.

He supposed that the Commodore Hotel on the cliff-top was far enough away for him not to be noticed, and even if he was he could make something up. He was good at that.

What would his father have thought of where matters stood? Standing matters. It was an odd phrase. He couldn't remember having taken anything to his father of a remotely personal sort, probably because he was his father's son, as unlikely to seek help in a crisis as to be offered it. His father, an amateur actor, was not the solicitous sort. Once, just turned teenage, he'd been taken to a performance of Dear Octopus, a play by Dodie Smith, at the pier theatre, and watched his father making up in front of a mirror fringed with naked light bulbs. He'd watched an inattentive man turn himself into a man attended to. This other character – rouged, Brilliantined black, and eyelined – turned to him as if to say, 'There – I am no longer me, no longer myself. I couldn't help you now even if I wanted to.' He learned later that 'octopus' referred to the tentacles from which no family could escape. Octopus – inhabitant of the deep.

​Emptying his holdall, he was startled by a noise at the window. It was a bird. He turned to see it coming at the glass again. Had it been the Eumenides, some blurred, wave-borne nemesis already on his tail? It amused him to think that his education - the voluntary submission to here-and-there learning that had given him gnawing waves and Greek frights – could do nothing for him now except offer up examples of daring and determination, blind to catastrophe.

​A car pulled up. Two men and a woman helped a much older man out of the back seat. The old man looked ill, or in pain, but wore a rosebud in the lapel of his jacket, as if being taken to a celebration against his will, a potentate dragged from his sick-bed to convince his followers that he was still compos mentis.

Lying back and staring at the ceiling, he heard muffled voices in the corridor, earnest at first then capped with laughter. A door opened and clicked shut and footsteps were retraced on soft pile almost in silence; ripples on water coming from nowhere then going for good. He'd told Moira he was leaving and had told her about the hotel. Moira – the 'other woman'. She'd half agreed to the subterfuge; now, he would hold her to it.

Cath had seen him alone with Moira twice, the second time at a window table in Starbucks at Worthing. She'd come in because Moira was their friend, once her colleague. He thought she'd seen him touching Moira's hand. He'd grown bolder, almost willing consequences he'd often only imagined. She hadn't mentioned it; but he could sense it polluting her steady demeanour, an unstoppable tumour signalling its presence in silly rows and resentments. Maddie, eight-year-old Maddie would have to be told; but he wouldn't do it, because there was no plan, no boxes to tick. So he scribbled one on the complimentary notepad, part-used, with the hotel logo stamped top right on each sheet: a three-masted sailing ship with a broadside of guns – a naval vessel.

Item: Ring Carl, to be put up. Item: Ring Moira to summon her: Item: Ring home (to speak to Cath then Maddie). Item: work, clothes. For it was true that – and he had the word for it – his departure had been precipitate, dramatic. Unlike his old man, he was a character in a drama of his own making; but like him he could pretend to be someone he was not, someone braver and more decisive.

But he crumpled the note into a ball and dropped it in the litter bin. He'd thought of leaving a note at home but no-one left notes, least of all ones in a sealed envelope leaning against the cookie jar. He'd phoned the dockyard to report sick. He'd text Cath then Moira; or Moira then Cath. And Carl. Before that, he was alone in his sea-gnawing world. Cath, Maddie and Moira were in the real world for now, especially Moira, his co-escapee to a land's end free of whispers and stolen acts.

Cath would soon be leaving her part-time job at Pink Angels and calling at her sister's to pick up Maddie after school. He imagined her tidying her desk, leaving everything in order. Once he'd texted them both, he'd be able to see the two dun-coloured ticks on the phone turning bright blue to denote receipt, a melancholic blue for go. From the room next door, maybe the one whose occupant had been trying to tap him an SOS, came the faint rise and fall of an excited TV quiz show audience or some comedy show, the convulsions spliced in.

He got up to investigate a mild commotion outside. A modern wedding party – not many guests, no wedding dress or bouquets, no bridesmaids, no maid of honour, no uniformity of style, no crowd, the bride with her toddler son; and the groom, accompanied by what looked like his slightly sickly twin brother but no stag night survivors. A sensible, cut-price affair, not like his and Cath's with its marquee and gazebo, speeches, guests they hardly knew, a disco, oldies jiving to Eminem, a honeymoon. The sick old man he'd seen was probably a guest arriving early, a tortoise pitched to the end of the race before the hares started out.

Maybe he should have phoned Carl first to make arrangements. Carl was one of his few close friends, but he couldn't predict the response. Carl was his and Cath's friend, equally. Might Carl not take Cath's side and remonstrate with him, try to make him re-consider? Carl was always diplomatic. He wondered if the conciliatory Carl always triumphed over the sympathetic one. He wondered why his mother and father had stuck together when they seemed so obviously mismatched, she always following him, never contradicting him, possibly fending off the attentions of other men.

Moira would be ready, waiting for his call, having connived at his theatrical flight to The Commodore's neutral ground, which faced the unknown but inviting. It was silly really; she'd giggled her agreement or ambivalence. He could have just moved in with her and sent just one email. No – not an email to Cath. He would have phoned, explained everything: that he had left, made the break. If he'd told her that night when he got home from work, far from sick, and she having collected Maddie and the two of them having spent the afternoon making fairy cakes for him, and Maddie sprinkling them with hundreds-and-thousands – it wouldn't have happened. He was weak. Cath had told him so during one of their fights. Getting out, leaving, was an act of strength, of resolution.

A man and a woman walked the corridor outside, joking together and stopping in silence – to kiss, he supposed, to snog – before fumbling with the door of a room, which closed as they fell against it and muffled their continuing merriment. It was then that the phone buzzed. It was Moira. He didn't answer. It was coming up to 5pm. He re-filled his holdall, tugged the bedspread flat, rang for a taxi to pick him up in half an hour, and went downstairs to the bar. The wedding party was milling around - anarchic, noisy and floral. His phone buzzed. It was a text from Cath: 'Where are you? What's the car doing here? Are you OK?' He replied that he'd explain later. Texting wasn't enough for Cath. She rang him. He saw it was her but didn't answer.

In the taxi, he phoned Moira but she didn't answer either, so he texted that he'd be with her in twenty minutes. He'd forgotten to hand in his hotel room key-card. He told her something had come up. He imagined the fairy cakes at home in neat rows on a tray, and, her mind racing, Cath with a cup of tea watching Pointless as Maddie sang and danced in her fantasy world on the rug in front of her.

He had a key to Moira's flat. He pressed the buzzer, looked around. Where was she this time? He let himself in. He'd let himself in when she wasn't there no end of times. And no end of times, she'd left a note in large marker-pen writing on the dining-table. There was one there this time too. It said: YOU'RE MAD. GONE SHOPPING. RING LATER X. Did it mean she'd ring him or that she wanted him to ring her? Did she know he'd bottle out? She must have.

He took the short walk into the town centre and caught a bus. Cath might have checked that the car wouldn't start, and it would. But so what?

She hadn't checked. He was on time for the daily homecoming and its little rituals: a peck kiss on the lips from Cath, a run-at-him hug from Maddie; and added to this time by Maddie's formal presentation of the cakes, the tray tilted upwards, her sprinkled creations crowding to her chest and almost falling off.

While the kettle boiled, he went out to the car. Cath couldn't see him from the house. He phoned Moira. If she'd come, he said, the deed would have been done; if he'd rung her (but she knew he wouldn't), she said, she might have (but wasn't sure). He told her they had one night left, all paid for. She was up for that. Later, on the way to collect her he passed the club, his usual Friday night destination; the car park was filling up. The headland lighthouse was sweeping the bay.

They'd got into bed, under the sheets, then cast them off. After she'd fallen into her post-coital sleep, he thought he heard the wedding party breaking up. Someone started singing; someone audibly shushed them. In the distance, like a rave in the countryside, the band could be heard coming and going. It was eleven o'clock. He gave her shoulder a gentle shake, and they got dressed and left.

When he arrived home, Cath was watching TV. As he passed her to sit at the far end of the settee, she held out her arm. He brushed past it. He lifted her feet to make space and laid them on his thighs. Without taking her eyes off the screen, she began rubbing her heel against him. He imagined it as a reminder to hand in the hotel key-card on his way to work next morning. Nothing else.

'Many there?' she asked.

​'The usual crowd of old salts,' he replied.