How do I get this girl, I dont want to lose her? Women please help mer?

Okay me and this girl has known about each other for years. Im 24 she is 22. We been seeing each other for 4 months. She has a kid and the father is in prison. He gets out in four months. She does have feelings for him. But he has cheated on het etc. so she meets me we end up seeing each other. I spend the weekends at her house. And she has even givin me a key. But when I ask her do u want me as a bf she always saus idk im torn. I know she loves me cus I did say I luv u and she says it back. I go about things extremly diffenrent then he would. Like he is jealous and trips on how she looks. So I got her hsir done ya know stuff like yhat to show im not jealous. Ive told her how iv felt and what o want. But she just tells me I do likeyou idk odk idk is her favorite friggin word. I am the one who is chasing her. She is smart and beautiful. Everyone hates him. And everyone likes me. I do **** for her all the time hoping to show her what kind of guy I am and what she could have. She just wont commit. Its crazywhy would she yell me all these things and give me a key to her house? I cant let go of her its crazy o know cus I think of I do and she does want to be with me, she can say o well gurss he didnt have patients. Im going crazy I love this girl and I deserve her not jailbait. I eant yo back up a bit but im afaid if I do then she will lose intrest. I cant plau hard to get cus she knows how I fell about het. Also she had a back up plan. All his pictures are hangin up still. I hate it. She told me she was done with him before I got with her. He knows about me. And now I think he is minipulatin her. She has these momenys where she is distant its bern likr this lately. How the hell do you ease up on a girl without her loding intrest. Plus she was like you are the best guy ive ever talk to. She got me its fuhkef up. He knocked her up two years ago and went to jail while she was prego. He is terrible and a loser he has been to prison twice. hrr fam told me not to give up