Somebody please explain!

Well for a little background ,me and my ex of 8 months brokeup because she said she didn't feel the same way about me and thought a break was the best thing, and this was because she started feeling an attraction for a guy...(there are other posts that have more info background if interested, just look through the posts)
Well today i found out some interesting news...I found out my ex broke w/the guy she was seeing(after breaking up w/me) after 2 months, and i was told, she cheated on him my going out with some other guy to a movie and now she is dating him(i believe, not sure)
Im so confused, i thought i new this girl, here bf before me was her first serious relationship and he cheated on her so she broke up with him because of it, and that the one thing she told me she would never do...
I was his her first and she told me after thinking about it she didnt really love her ex, but she did love me really...and i thought i new her well and this seems so out of character of her, im s confused!
The last time i contacted her i asked her to meet up as friends and she said ok but never did, so i responded that, if you can take a little time for to meet up i see how much you value our friendship, she responded saying..."youre the one that said you didnt want to be friends!"
Well i thought that was the last of it and then i went to a watch a highschool wrestling meet(there was a basketball next door at same time, where she was), and i guess she new i was there so she responded stating, can i say hi to you, i replied do what you wish, and I just ended up leving b/c i didnt really want to see her...but i found out today that she was their with her "new boy friend"...
Im sorry for all the posting and that its so out of place and confusing, but im just so confused, what is happening to this girl, she never did give me a reason for breaking up, she said she wasn't sure how she felt, but now she is just doing things like this, should i maybe talk to her, or what should i think of all this?
Thanks a bunch in advanced

She is simply not the girl you feel in love with right now or maybe it was there all the time and you were blinded thats all. That ok it takes a while to ge tto know someone ya know and there are always things that happen and different roads to take. I say consider yourself lucky and now it is time for you to let go. This should be enough for you. Do not try to com einto her life anymore live yours all things take time. Give yourself that finally. Put this to rest and behind you! Good luck

thanks blue... i appreciate you taking the time to reply