Anyway, Chris had been well stocked on that train ride and, by the time we pulled into the station at Guildford, I was three double gins to the wind and a little fuzzy. I have hazy memories of dinner in a small Italian bistro at the top of the high street and a chaste kiss at the door to my flat. He had asked if he could come in and I had feigned mock horror before exclaiming that I wasn’t “that type of girl.”

For the record, I wasn’t any kind of girl, not consistently anyway; I’d had my fair share of spontaneous and ill-advised trysts over the years. But something screamed at me through the gin and the wine not to let him into the flat that night.

In the morning, head pounding, I had found a handful of texts from him, begging to see me again. At the time, I had thought that inner voice was my guardian angel making sure I followed the three-date rule. Thought that perhaps this man would be “the one” and I shouldn’t jump into bed with him so quickly or he would think less of me, or some such bullshit.

Or perhaps it was my guardian angel. Screaming at me to NEVER let him into the flat.

Chris graduated from train stranger to boyfriend, then fiancé, and eventually husband. He never pushed me to talk about my family or demanded he meet any of them, except Mum. He knew what a crazy fucked-up group of idiots they were and let me leave them to it.

So how had he met Leah without me? How long had they known each other? How many times had she been to my house, sat on my sofa, lain on my bed? I say “on” rather than “in”: Chris is not an under-the-covers kind of guy; he is a full-lights-on-and-fingers-crossed-there’s-a-mirror kind of lover. At first it was hot. Now I feel like a performing seal who just wants to go to bed with a hot chocolate and read a book about other people’s hot romances.

Had Chris tracked her down just to mess with me? Or had Leah been the hunter? There is a part of me that always wondered what Leah would do to eventually bring my world down. I need to find out the truth.

Her Instagram is full of pictures of brunch, and the interiors of black cabs, and her peering over a pair of glasses—most likely fake as I assume her vision is as 20/20 as mine—with hashtags like #workinggirl, #gottamakealiving, #business-bitchesthatbrunch and a whole load of other banal shit that I absolutely detest. I struggle to find a way to break up the string of letters into sensible words. My twin, however, has made a living from this. When she says “business bitches” she is literally meaning other women, like her, who swan around not actually doing any work at all. But still, from the sound of it she is tired and strung out and #inneedofheadspace. Her last message is signed off with an apology that she is taking a few days out, to #decompress and #findherself, and that she won’t be posting for a while. #homeiswheretheheartis. That’s her last status. I know exactly where she will be.