I've been in exactly this situation.
Good friends with a guy who over the last 18 months has told me he thinks I'm lovely, that I look fantastic, came right out and asked me if I was single (I was mid separation at the time and over the next few months kept asking how the separation was going)
Then we progressed to dating even though we never called it dating. So cinema, lunches, gym visits, skating, dinners. Spent a lot of time together. We get on so well, loads in common. It seemed more than friends to me, he'd text and say he was getting snacks for us both, etc for cinema trips. We'd hug and pecks on the cheek but nothing more......but there seemed (or I thought there was) chemistry and some flirting. We were meeting up 4-5 times a week.
So in the end I told him how I felt and asked what was going on. His exact words were "there's no attraction".
I was gutted. I'm questioning myself is it physical or a personality thing. Am I not slim enough, not blonde enough, not pretty enough, am I not funny enough, do I talk to much?
My head tells me I should not bother with a bloke who makes me question myself so much.
Then a few days ago he told a mutual friend that he was really sad that he'd lost me as a friend as things were now awkward between us. Said it wasn't often you find someone you have so much in common with, etc.
I've texted him and said I don't want to lose him as a friend and that if we can go back to that I won't read too much into our friendship and that I obviously misread the situation before. He texted back saying he wants to stay friends. Which is good, but does lead me to think it must be a lack of physical attraction. Which I can't really change I guess. But I'm quite heartbroken.