Girlfriend gaining weight?

I started dating my gf 5 years ago. She is very beautiful and curvy. However, the entire time we have been dating she has neglected to live a healthy life style. She eats decently at best and she rarely works out. Because of this she has gained 30 pounds since we started dating. Recently I have lost some of my attraction to her. Because she added 10 pounds out of no where and it's lost some of my attraction. I have asked her to start a routine of working out. It's not even that she herself is the only person that needs to workout. Everyone should workout. And I think with the recent weight gain starting a routine of working out would help her get start getting back to a beautiful fit figure. We are at different colleges so I can't be with her to have her go workout with me. She has to do it on her own. And she has neglected getting into a routine. Moreover, everytime I ask her if she worked out today she gets pissed at me and tells me to stop asking (cause most days she didn't). when she does workout though she looks awesome and I always tell her that. I love my gf we are so compatible but recently I have been losing physical attraction to her and that is something that is needed for my happiness.

What do you think I should do? Mind you I do not see myself with her in the future if she continues these unhealthy life style choices.