Mr. Answer Man says: Ex-girlfriends are difficult for a guy to talk about. There's an emotional calculus that happens, and it goes something like this:
you + guy = strong feelings and
old girlfriend + guy = strong feelings
but
old girlfriend ≠ you
Do you see what I'm saying? You've put him into a double bind by asking him to remember a time when the feelings he's currently focusing on you were focused on someone else. And because he wants to be with you now, memories of those former girlfriends feel like a threat to his current feelings for you. The irony is that if he clams up, it's not to exclude you, but to protect your relationship. A good thing to keep in mind if you explore this.
So, if you just have to know, go slowly, and for God's sake, if he's resistant, don't push. Mr. Answer Man also recommends examining your own motives. What exactly do you imagine this information will do for you?
Let us know what you think and ask your own questions here.
Find more Mr. Answer Man here.
Are you obsessed with his past? See the Dating Doyenne's advice here.
Then get more expert ex advice:
Is He "Just Friends" with His Ex?
Found a Letter to His Ex: What Now?
Should I Invite His Ex into Our Home?