Does anyone recognise this book?

[GalileoHumpkins]

I've been wracking my brain trying to remember this book, I must have read it in the early 2000s when I was in my chick-lit phase.
MMC was a gay man who decides to try a relationship with a woman (sounds awful in retrospect!) and falls for his best friend, I think they end up marrying and having a baby.
Written by a male author and was extremely popular at the time, I'm not sure it's something I'd want to read now but it's bugging me that I can't remember the title.

Sounds like the TV series Bob and Rose starring Alan Davies. Is it definitely a book you’re remembering?

Definitely a book, that's not a series I've heard of.

Mike Gayle was a male author who wrote chicklit style books around that time, might be one of his?

I've looked at his but nothing's ringing a bell, maybe I'm misremembering something.

Our way or it was love?

The Object of My Affection? There was a film too with Jennifer Aniston and Paul Rudd.

Nick Hornby?

I had a book like this, I felt as though it had a blue or green cover, and I thought it was turned into a film, possibly with Madonna in it, Googling gives me The Next Best Thing, but I'm not sure that's familiar. I think I would've read it in the 90s. Frustrating!

Tony parsons?

I think this is what I was thinking of, the hardback version is green and yellow! https://www.abebooks.co.uk/servlet/SearchResults?isbn=9780333449486&n=100121503&cmsp=mbc---ISBN--used