I think my exgf knew before I did that I wasn't all straight. The thing is I feel bad for leading her on before I knew. We dated for four years and it's been two years since we broke up and like you can see just now am I looking to sort out the details and come out. I've told her first that my gender identity is fluid. She took it well although I could see tears in her eyes. She said she would love me even if I was gay (to her bi and gay is the same). I haven't specified my sexual orientation, because I don't know, but I fear the most in the world that she will doubt the love I had for her. She's been supportive these days, but it feels like the spell has been broken. Before I told her it has felt as if we still love each other and are still dating. Now it feels like we're two people who have known each other for a long time. I don't know how this must be for a straight girl. We were each other's first. And although she and I know that other orientations are natural and not wrong, I still wish I could have been the man she dreamt I was.
You shouldn't feel bad. If you didn't know that you were, or suspected that you were gay or bi, and you loved her (which you obviously do) then there is no way that you were leading her on. You just have to remember that it will take her a while to adjust and accept, and that the love you had for each other is still there its just a different sort of love.
All I could do for my ex wife was to continue to support her. The most important thing I did was to work on myself. She needed to see me get better so that I could be a good father for our children. So you need to just keep working on your own acceptance. The way you're feeling about the two of you now is quite normal and natural. You should feel like two people who have known each other for a long time. You should feel like good friends - not ex's. Good luck!