Alienboy wrote:
Well I know her pretty well and that she is mentally unstable when she is stressed out. It was strange because she was online for a long time and so was I and I said hello is everything ok and she completely ignored me it was strange because when I hangout with her and my friend she is really nice to me...
It's hard enough to judge if she likes you in person. So I wouldn't overcomplicate things. In social situations, the simple answer tends to be the right one. In my experience anyway.
Most likely the things aren't related. She added you because you're hanging out a lot recently. She ranted the next day about something stupid he did or did not do with no thought as to you being a new friend on facebook. And she most likely ignored you online because she either didn't notice you were there, or got busy.
Or you missed a conversation que. If you say hi, and then she says hi, that usually means it's your turn to talk. And if she's not interested in talking to you per se, or generally preoccupied (having a chat argument with her boyfriend, in-person argument, or, umm, makeup time), she most likely won't try to engage conversation with you.
It's hard to step back and think about things that way, but it is an essential skill. It helps if I think about times I've been in a situation similar to the other person. I.E. "Why wouldn't I talk to a friend online? Well, when I was talking to my girlfriend when we were about to break up and..."
The biggest rule i've learned is that "99% of people think about you less than 1% of the time." Strange behaviour is oft times best puzzled out by taking yourself out of the equation entirely.