My bf is having trouble with this at the moment. He doesn't know what to say to me. So his method is by keeping things light and just talking to me and making little jokes. It's not that's he's ignoring that I'm sad or anything, it's just he doesn't know what to say to make me feel better, so he tries to keep things light and joke with me a little to make me smile. He'll say sweet things too...
I'm not sure if that helps because everyone is different, but it works with me :/ And sometimes I feel like a burden and that I'm hurting him, but when we're together and he keeps things light and jokes with me and tells me he loves me and stuff, it does make me feel better.
Or maybe try the honest route? That you're only hurting because she pushes you away, that you love spending time with her and being with her etc....?
I don't know if any of this helps >_<