[Dominic]

Look, A lot of people are going to tell you you're awful, you're shallow, you shouldn't care about her weight since I'm sure she's beautiful on the INSIDE.

Bullcrap.

She must know how you feel about fitness and keeping in shape, and how important they are to you. She also must know what you like physically, and that her gaining weight probably turn you off. Ten pounds on a 5'1" girl is a lot...and I'm sure she's gained more than that, correct?

What does it say about her that she doesn't care enough about you to realize these things are important to you? You're very young and shouldn't be tied down to someone you're not physically attracted to.

Women have to start realizing that men are visual creatures. They can't gain 30 or 40 pounds and then expect us to want to keep boinking them.

I'd sit her down, tell her your concerns and go from there. Either she'll understand and start taking better care of herself or she'll wig out and break up with you.

Win, win, I say.