General

I agree what everyone says about just treat a BBW like you would treat anyone else.

However, try a BBW dating service, or answer a BBW ad in a regular dating service.

She may look different than the thin women you date, but the hooking up part is still the same. If there is chemistry and you have things in common, then it will work out. Once you have that connection, you can possibly discuss BBW issues and let her know you like her physically too.

there are several things i can think of, but they could be wrong as well

1) it could be possible that you've been seen with skinny girls to often, and the big girls can think that your not interested in them in that way

2) the big girls just could be plain shy, and don't expect very quickly that someone has interests in them

3) they crowd you hang with give off a negative vibe for fat girls. If your mates have skinny gf, i assume it can be quite intimidating for a non skinny girl to fit in.

and again, since i know very little of your situation, these could all be very wrong.

you could try being a little more direct in that your interested, but it's your better judgment to decide if it's in place or not to do that.

good luck with this