advice and suggestions plz lol?, stuck here lol Options

[LostRenaissance]

Well first thx for u guys taking ur time reading this lol. k so.
It started off as me going to prom with one of her good friends and then when school started i started to like this girl. At the beginng it was jsut like ah w/e but as time moves on i started to like her more and more. K here's the problem she started going out with this guy a few days before school started but he's in california. So me and her chilled together and stuff when homcoming came we spent the entire nite together and when we sent her home she kissed me on the cheeks before she left.
Then Halloween came me and her friends when to a freight fest, during the hunted hay ride i put my hand on her shoudler cuz she was realyl scared but before i pulled away she grabbed it half way through the freight fest cuz the girl i when to prom with couldn't go and she was sorta crying i called her up to cheer her up and ditched the group for a bit but when i got back she started to avoid me. I spent msot of the ntie trying ot find out why it wasn;t till 2 days later she finaly texted me and told me she was okay... later i found out from her friend that she was mad cuz i ditched the group to call the other girl. but she has a bf why would she care...
I started to hang out with her more and her friends more and we got really close and since my best friend is dating her best friend we spent alot of time together, us 4 hanged out alot.
So her birthday came i got her a nacklace for her birthday and a matching brancelet for christmas us 4 me her and her best and my best friend when out for christmas and we had dinenr at a really high class restarunt seems liek she enjoyed herself.
I had a terriable childhood and such friends is the only thing i got and i really really like her i dun think for the past 2 month i fellen asleep once without tearing even if a lil about her. I dun wanna go break her and her bf up just so i can go out with her but i can't seem to get her off my mind... but she seems to change at times she's sort of different in school then when we're by ourselves. She acts colder towards me in school but while when we're in a gathering or something she's seems to be alot closer to me.
i dunno if i should go ask her out she and her bf spents most of the time together on mic phone and phone everyday after school and stuff. and when she talks to me about their relationship and stuff she's sort of unsure because he loves her more then she likes him back. But i dun really know if i should go ask her out or something... i dun wanna lose her as a friend or anything... And she's leaving at the end of the year since she's a senior and i'm a junior....

srry for blahing so long srry.. i didn't know who to ask so if someone would gimme some suggestions it'll be a great help. thx
~Lost