Does she like me or am I just wanting to believe?

Right i have posted something similar to this before but not with as much detail.

simple - i like this girl that i have known for two years. We used to sit next to each other in class and talked in every lesson this occured. Recently she found out that i liked her and she told her best friend and my best friend how she wanted me to talk to her more as there may be a chance and also told them how she doesnt know me very well.

1st problem - she is one of my friends ex, although she talks to me and said that she would never get back with him because of how much of a flirt and how arrogant he is and this has led to us falling out although it is all just jealousy on his part. For example today when i was talking to her he would come up and put his arm round her and speak but me and this girl both feel very awkward as if to say please go away.

2nd problem - She hasnt approached me much before but today not only did she approach me the first time she saw me but also approached me again when we walked to the same lesson together.

Do you think she likes me or not? any help is appreciated

If you ask her out on a date and she says yes, that means she likes you. You won't know until you make a move. Or you could just ask her if she likes you but that's kind of dorky and way unsmooth so don't do that.

I was never a one to meddle with my friends exes - I wasn't that keen to have their 'sloppy seconds'...lol. How long has she and your friend been split up? You say you have been talking to her and for 2 years. Were you living in hopes of getting with her and while she was with your friend?