An old friend whom I saw last year has sent me a text asking if I would like to go out for a drink. I can't remember if, when we met at the party, I told him I was newly single. All the same, he was more handsome, cleverer and funnier than I remembered him to be in our teens. All of the things I might put in the "looking for" section of online dating blurb.

The text is a year too late. But last year it was a few months too early because all I could think of was R.

A few weeks after we split, out of a vain sense of curiosity over how many enquiries I might receive, I signed up to a dating website. Within minutes I had created a profile and sat back satisfied that I'd avoided cliche in the "About" section, and uploaded a photograph that actually resembled me.

As I clicked on to the website I saw, to my horror, that my photograph appeared in a sidebar alongside the main news page of a very popular website. I had also, in error, used my real name as my username and it appeared in leering capital letters next to my picture.

With all the words fused together, the suffix 34F (age, gender; terrible box-filling error) made it seem like I was flaunting my chest size like a glamour model. After a flustered 10 minutes trying to find the "delete my account" section on the site, I disappeared. Possibly the quickest debut and end to the search for new relationships the world has ever seen.

But now – to this old friend who essentially might be a good suitor if I wasn't otherwise married – I wonder what I should reply? I've always been far more comfortable with receiving rejection rather than handing it out. He is only asking me out for a drink, and yet I still do the thing that marks me out as a coward: I tell him I'm working abroad for two months.

Part of me knows that this is because I find it hard to be honest. Most people might say: "Would have been great but I'm actually back with someone now." But I keep it vague, perhaps because part of me thinks that if R were to royally mess up and become the impossible drunken husband again, then the chances of finding a sure-fire happy date to get over the heartache of not being with him any more would be hard to stumble upon, and oh, wouldn't a drink with a nice, funny, handsome, clever old friend, be a rather lovely antidote to post-relationship misery?

Then there's the awful admission somewhere in my mind that I'd like to go for a drink with my old friend and tell no one. That I'd like to do something a little risque, a tad secret, a bit daring and very dishonest, with the forethought that it was morally OK because we would only be chatting and at the end of the evening I would turn to him and say, "That was lovely but I probably forgot to mention that I am still married."

Which is far madder than anything you could think up, I know.

The truth is, I miss doing bad things. Most of the time it feels good being good: I like to wake up with a relatively clear head; I'm able to move from one day to the next without always catastrophising a situation; I mostly manage to avoid the self-admonishment that results in me eating half a cake or telling the children to bugger off.

R admitted last week that he found being sober tiresome. What followed was a series of lugubrious days of us trying to avoid each other because we realised that we'd reached some sort of recovery zenith, and it was pretty bloody boring. There was no peak at which to feel jubilant. Early days it is, but I sometimes feel in 20 years we will have to mark whatever progress has been made with a less than remarkable "This is it, folks!" plaque.

Optimism is a hard one for anybody in recovery. In the slow days, it's like reminiscing about a long-term relationship with someone you once loved passionately, who was not good for you in the end, and who you decided to stop seeing but still adored. The aching heart won't abate. Sometimes a song or a smell or a city will remind you of all that you had. And you will feel the intense loss over and over, every time the memory is reignited. I know R feels this. And I feel it too.

We both miss being free, and sometimes we miss being bad. While a drink or a kiss with somebody new won't make us feel any better in the long term, there's no denying that it could be fun.