Rhodri Marsden: You may choose to call me Noggle. But I may not respond kindly

I idly looked up the seven deadly sins the other day. They read like a checklist of my day-to-day life, a series of emotions and activities that I cycle through rapidly – or, in the case of sloth, bloody slowly. Take away my seven deadly sins, I thought, and all I'll have left is sipping tap-water and vacuuming. Envy is currently looming particularly large; I'm usually delighted for people when they achieve success, but as a single person I inevitably have periods where the cavorting of happy couples makes me grit my teeth. The only happy couple I can tolerate is my mum and dad, and even that's a bit of a strain. (Mum, if you're reading, that was just a punchline, honest, everything's fine.) Any overt displays of public affection provoke the kind of burning resentment that wrongly convicted criminals must feel as they languish in prison, knowing that the person who actually did it is on a once-in-a-lifetime Caribbean cruise.

An email arrived midweek from a girl whom I don't know very well but who had nevertheless anticipated my pressing need for solidarity. It contained the single word "VOMIT", and attached was a screengrab from Facebook featuring two of her loved-up friends exchanging public messages of sickening sentimentality. "Hello Mrs Picklehead," read one. "I am Mr Picklehead." Man alive. But for all the abuse we might privately hurl at this kind of thing, we all have the capacity to become hopelessly lost in the world where Cuddlesaurus and Snugglepotamus are acceptable modes of address. We may fight it, as an ex-girlfriend and I did by sarcastically referring to each other as "Noggle". But the sarcasm eventually disappeared, the name stuck, and "Noggle" we became.

At least we kept that to ourselves. Recently, I sat on the London Underground opposite an infatuated couple who were frantically pawing at each other, oblivious to the fact that I was blasting away at them with an imaginary firearm. Then another couple got on, bickering, flustered and furious. "Get off me," she snapped, turning away from him sharply. I suddenly stopped my merciless assault on the canoodlers, thinking actually, these are fleeting, precious moments. We should probably grab them while we can – even if it is on the Northern Line. My envy then segued neatly into gluttony as I ate a Kit Kat.

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