X represents a variable amount; an unknown quantity; God knows what, particularly if it's appended to the end of a text message.

Invented in the mid-18th century as a supposed equivalent of a kiss to be added to written correspondence, it carries far more weight these days. In an era of rapid-fire message exchange, it's become a weapon of flirtation to be deployed – ruthlessly – in a series of manoeuvres more complex than landing infantry on a beachhead during amphibious warfare. No amount of algebraic analysis can ever uncover the true significance (or otherwise) of X, or XX, or an absence of X, and I've given up trying to understand it.

A couple of years ago I had a brief encounter with a girl whose persistent addition of XXX to the end of her communications gave me an gloriously optimistic outlook on our potential relationship. This was misguided; I soon realised that she added XXX to every message she sent, regardless of any affection she might have for the recipient, eg Southwark Council. A few months later, I quizzed her about this and she explained that XXX was her standard sign-off because it gave her room to show displeasure by removing them. Withdrawal of all three kisses represented the ultimate insult, like flinging some kind of digital shoe. It's not a bad strategy and it makes sense when explained, but she didn't give me a reference guide when we met, so working out the cipher played havoc with my emotions.

I retain the bad habit of adding an X as an exploratory venture to see if it's reciprocated. It's laughable. What I'm essentially saying at the end of every message is: "I think you're nice, do you think I'm nice?" I'm not even 13 years old. I'm 40.

Anyway, the reason I'm blathering on about this is because I'm currently having text-tennis with a girl and we recently doubled up from a single X to a thrilling XX, which would under normal circumstances mean that we'd be getting married at some point, except I've learned that she's emigrating next Monday. So I'm confused. The X is tormenting me. I might take a leaf out of my friend Michele's book; she always uses a tilde (~) instead as a form of protest. Or I might just revert to "yours sincerely". You know where you are with "yours sincerely". Love, Rhodri X

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