so here is my situation; i made a new friend at the beginning of the school year and we have been hanging out and such an i learned that she has had a reasonablely difficult life and for the past two years has had no stable friends because of bad luck and past enemies and she has fallen into a pattern of falling in love with anyone who is nice to her for a reasonable amount of time which has caused believe able speculation that she likes me which would not be an issue if i was not already committed in love to another person but i do not want to hurt her and i want to help her break the cycle of love than depression repeated so how should i approach and stop the situation without restarting the cycle and still be her friend. i am sorry if reading this was a waste of your time

ohh, bad story. And complicated...
That is what girls usually do. From what I get from her personality, I can tell you this: try to not tell her directly. She might suicide or who knows?
You felt pity for her, but you can't tell her this. I, as a girl, hate when a boy feels pity for me. So I know what I'm saying.
You need to encourage her to be social and if you see that she has even the slightest crush on someone, just push her toward that boy. Encourage her on going to talk to that other guy.

Or tell her directly that you love someone else. And tell her that what she feels is not love. It's just gratitude. She is just happy someone talks to her. But, please,if you do so, try to be her friend.

Is it worst when the person you love rejects you and then ignores you. She might be upset for a while, but eventually she will see you are a good friend and she will be happy about it.

thank you very much for the advice i will be sure to approach this matter with extreme caution.