I've been meaning to post on this thread for the last few days but can't get my head in the right spot, thankfully though Alice has been great.
One former great poster around here used to say something along the lines of, if you are thin, fit or fat, you will always find people who find you attractive that way. He also said that if you want to attract a person while thin, why would they still be attracted to you if you got fat? People will be attracted to what they see, so if you are already fat, people who are attracted to you will have less problem with that then someone attracted to you while you were thin and then finds out you'd really rather be fat.
I know its so much easier said then done, but I think its good advice that is at least worth considering.
Good Luck, I struggle with the same dilemma.