I can relate a lot to this post. My best friend tells me that I am not as outgoing as she is and that's why more guys seek her out. I'm not sure if she's right, but it's one possible explanation why guys tend to go for your friends or other people more so over you.
I guess we don't realize much how we put forth, but I've been recently told I'm cold and I never thought so. :/
Maybe try a dating site? That way you can get to know them closely before having to actually meet them and be social.
Hope this helps!