what makes a friend

I sometimes wonder if I'm too picky when it comes to having friends. I've never belonged to a "group"... and when I think about the friends I have now getting together in one room, well, it would be odd. This girl has been stopping by every few weeks for a chat, and ultimately I knew she wanted to give me a speel about her work which is promoting some financial company through talking to their friends and trying to get them on board to do the same thing. Very annoying. But I listened. I couldn't talk her out of leaving me 2 tickets to a corporate profile lecture, but I didn't go. And I don't feel I'll ever connect with her on a friend level. I don't feel I could ever confide in her with anything personal, and ultimately, if I can do that, I can count that person as a friend.

When she came to visit me this last time she was wearing a ring on her "marriage" finger. She'd just come back from 5 days in Texas with her new boyfriend so I asked her what it was, and she said it was just a ring she practically always wore (that I'd never seen her wear before, and I'm a complete jewelery gawker) to remind her that she's " no man's woman". Yet a month ago she flat-out CAUGHT the guy she's still with cheating on her (through seeing stuff on his phone, etc.). I could go on but that's the gist and I have to run for a visit to the in-laws. But basically, I just don't get either of those ways of thinking... being no man's woman yet staying with someone who cheated on you. Either of those, and especially both together. I just don't get it.