I may be the wrong person to ask about these matters - but I do have an interesting question to throw out...
....but were you even friends before you became BF/GF?
I only ask because well...I honestly don't remember ever really being friends with someone until after we dated once or twice and then decided we wanted to "be an item." Weird.
Anyway, no, I don't keep in touch with anyone I used to date. The only one I would even consider doing so with would be my high school boyfriend, because he was the closest to a friend that there was. He was a good guy, very family driven, very. VERY religious. Clean cut, trustworthy, dependable. We just had nothing in common when it came to interests. He was into cars and music and bands, and I had no desire of being dragged along to concerts and auto shows...LOL. Ah, there was a lot involved but I cut him loose. I do hope he's doing well though, and that he's found someone he can love.
There is also another guy that I am friends with, but surprise surprise - I never dated him...LOL!
Interesting thread.