He should have just let it go. Of course it was just a joke, something to fill the impending silence as they traversed the utter boringness of deep space. But no, he had to open his smegging mouth and now he was here, alone, in the cargo-hold. The conversation just kept replaying in his mind: the Cat, Kryten, and Lister.

"You know with our luck, I don't think we're gonna run into any ladies ever." The Cat had said, while steering the ship.
"Don't worry sir, if you can't find a lady any time soon there's always Mr. Lister." Kryten had added, and Rimmer still couldn't tell if he was being serious or not.
"Well there are worse things I suppose." Lister shrugged.
"Sorry bud, but I'm a strictly 'ladies-only' cat."
"Even with your fashion sense?" Lister had laughed. Rimmer still thought he'd made a good point.
"What you talkin' bout, monkey? You interested? 'Cause I know I look damn good and all but I ain't going there."
Lister put on a (in hindsight, faked) pained expression and put his hands on his chest.
"Aww, you've broken me heart. C'mon, give's a kiss…" Lister had teased, as the Cat rolled his eyes.

This was where Rimmer knew he should have just let them laugh and allow the subject to be dropped. But no, he had gotten jealous and snapped back.

"No! You're not seriously in love with the Cat are you?" He asked incredulously, with a hint of anger.
"What's it to you, Rimmer?" Dave responded, trying to drag some amusement out of his friend.
"Well just because your boat swings both ways doesn't mean you have to settle for him when there are other people out there better for you! I mean, could you imagine kissing that fish-breathed narcissistic, self-involved cat?"
"Ok ok calm down Rimmer – we were only joking. …Why weren't you?" Lister responded questioningly…well, Rimmer had heard it as 'accusingly' at the time. Even here he could have just said that he was joking too. But no.

"I… I… Because Lister deserves to be with someone that treats him right, cares for him, looks after him…and clearly that's not you, Cat." He had snapped.
"Hang on, you said there were other people out there for me. But I'm the last human alive, and you're the only other one around…Rimmer, did you mean you?"

This was where the joke had ended, with all three of them staring at him. Even then, he supposed, he could have laughed and lied. But instead, he had gone pale and ran. Right to the cargo-hold. And he had stayed there, uttering 'smeg' to himself over and over with his head in his hands.