Help... girl problems...?

I have recently met this girl... she is the most amazing girl I have met in a long time... I like her alot, and she says she likes me... theres just one problem... she has a boyfriend...

My good friend who is also friends with her told me that her and her boyfriend are having problems... which leaves several possibilities... 1) I have a shot (something that I usually dont have with girls as most find me repulsive... yet im one of the few guys after love and not sex), 2) They make up and im left on my own again... 3) She uses me to get back at her boyfriend...

with my luck, it would be 2 or 3 that happens...

theres just also one more bit of info... she has a baby... I dont know if it is with her current boyfriend or not, but I dont know what to do... I like her ALOT... maybe even love her... but I dont want to get in between her and the father of her son...

last night we were at an all nighter event with a bunch of friends, and her and I had a blast... we sat together the whole time, we hung out, it was fun. but when I heard her mention her boyfriend, my heart sank... atleast for a bit... on the bus ride home, she fell asleep on my shoulder... I wanted so bad to put my arm around her and hold her, but was afraid id be crossing boundaries... turns out she was dissappointed I didnt x.x ... Also, when we stopped at McDonalds for breakfast, another friend of mine pushed me to put my arms around her because she was cold and sick... I wanted to, but again didnt want to push boundaries... but ended up putting one arm around her for a moment... at first I was upset with my friend, but then upset with myself when she told me she loved it... upset with my self that I didnt give her all I could have given...

haha I realise I havent really asked my question yet. What I want to ask is what should I do? I invited her to a movie saturday, but that could end up being a just friends thing anyway... should I go through with it and risk more heart break...? should I risk getting between her and the father of her baby...? Im 16, and turn 17 a month after she turns 18... I look through her pictures and see her with her boyfriend and I feel sick in my stumouch, worrying what I would be doing to him or if she is using me to backstab him...

what on earth should I do?