Me [30 M] with my FWB [27/F] of a few months. She wants more but I'm not physically attracted.

I met this girl around three months ago on tinder. We've been hanging out and I think she's awesome. We both have a weird/fucked up sense of humor and we get along great. I can tell she's starting to fall for me and I am starting to really like her as well.

The problem is she's pretty overweight and I'm just not that attracted to her. She's really pretty and could be a 10 but she has no desire to get in shape at all. I'm really heathy and in great shape- she always makes fun of me for going to the gym and eating choices- which is funny to me.

But I feel like we're about to have a big "defining the relationship" talk and I don't know if I should just be honest with her or even how to go about it. I'd be more than happy to help her get in shape if she was willing.

tl;dr: Unattracted to FWB- were both catching feelings.