My girlfriend of 4 years became fat, I've tried everything but she doesn't seem to care enough to put real effort into being thin.

I think because she's a good girl, I took her virginity and she has a good career I have trouble letting go. I don't think I'll ever find this combination again.

I was told I needed abundance, so I slept with 6 attractive girls and I still can't bring myself to break up. The sex with those girls was awesome and I felt awesome but I still can't do it.

What can I do?