Need some advice here from mature women an guys please?

im 16, an i like this girl i know for a couple of months already, shes 17, an haves a bf. an the first couple of weeks when i met her i didnt know she had a bf. an i kinda started to like her alot. we text everyday all day. shes very cool, an pretty. but then she told me she had a bf later. ever since that time i met her i couldnt stop thinking about her alot. i really want her. i know ill make her happy for the rest of her life. an no im not sprung but i just like her. out of all the girls i had, this one is to keep, shes very smart, she goen to school, she thinks about her career an what she wants to do, i mean shes a keeper you know. an her bf, im not talking crap but i dont think he deserves her, they sometimes get mad at each other, he doesnt work an i do, hes a gangster, an im not, all he cares about is his homies an gang, she always buys him clothes an everything its like wtf??you know,lol i told her i want to be a marine an she thinks thats awesome. this one time she thought i was mad at her an she told me if was mad, she was worried, my sister in law told me she talks about me alot. i dot know tho, shes been with him for 2 years, i guess she kinda knows i like her, but i dont want her to know bcuz then they get all concited with one, but yea i talk to her as a friend an joke with her too just like a friend but deep down i like her more.. i dont know ppl.Need some advice here from mature women an guys please?
girls are always drawn to the bad guys, trust me years down the line when you're running your company and her boyfriend is in jail, she is going to wish she had given you a chance, don't do anything women always want what they can't have......