They say a photo is worth a thousand pounds...err...words.
Come on, if you're expecting 150 and get 250 and it's deal breaker, you simply ain't doing enough groundwork, also know as being direct, asking questions, before you head off to the marina...err...date meeting place.
On top of that, what if the girl of all your dreams, I mean everything, just happens to be overweight? Maybe you, being the man of her dreams, simply needs you in her life to be motivated to care enough to take good care of herself and, a year or two later, she is in great shape? Because of you?
Weight is one thing. You, she, can't fix personality, preferences, views on money, sex, religion, family, etc. If you can't fix stupid, you also can't fix someone who is ugly on the inside no matter how hot she is on the outside and that goes both ways.