I'm in the same boat as you,
Strange Famous (well, not exactly, I weigh ~275 but I'm 6'1", a fair amount taller than you).
I think my problem is I'm not very self-confident; specifically, I don't reach out to random women even if we have something in common, like we share a class or something. There are some underlying problems keeping me from changing this, but I am (slowly) addressing them.
I'm quite sure it has little or nothing to do with my body frame. Which, incidentally, I'm also working on changing.
I think this is the attitude that you need, if you want to meet women. It helps a lot if you aren't a "stranger", though.