Maybe you should just call her up, say, "I just wanted to touch base with you and see how you're doing." And take it from there...maybe if it's going well, see if she wants to get a coffee and catch up. If it goes poorly, then just let go. Maybe say, "it's been really nice knowing you. I'm glad we had the time together that we had."
One thing that's a little different with your situation is the gender situation. It wouldn't be such a problem, except your girlfriend is unsure of her sexual orientation. When I put myself in her shoes: If I had a gay relationship, but then decided it wasn't right for me...or maybe that I felt I wasn't gay....I wouldn't want to be pursued by my former lover. But, maybe you can lay the groundwork to be friends, if nothing else, and never be "girlfriends" in that way again. Would you be good with that....just friends?
In the end, it's not the years in your life that count. It's the life in your years. Abraham Lincoln
It is hard to fail, but it is worse never to have tried to succeed. Theodore Roosevelt
