Help! what do i do now?

There is this girl that i met since the first day of high school. i began to like her after 3 or 4 weeks of just having small talk in class. i only hung out with her once then lost interest. im now a sophmore and i have begun to talk to her again. during which she has lost all of her friends because of some drama, and she started to become better friends with me. at this point i have completely fallen in love with her, but at the same time she has a BF. she tells me that he hits her, (not often) tells her she isnt fun anymore, and treats her like shit (he didnt even get her anything for valentines day!) i told her my feelings for her, and while i did she never really told me she didnt like me, she just said i dont look at dating other guys while i have a bf. one day my friend asked her if she liked me, and she said i wasnt her type and stuff. this making me sad i texted her saying "why dont you like me?" (stupid) she asked me "why would you like me, i have issues" and i gave her a really mushy from the bottom of my heart answer and she said that she didnt want to date anyone, because she is afraid that she will get hurt again, but she also says that she cant leave her current bf. she doesnt know why she cant she says.i told her i would never hurt her, but she just said she doesnt want to date anyone but said Bf. i am really scared now because i am afraid that our friendship is in danger, and i am very depressed because i am lonely. what do i now?