<human>: I (22M) have this girl (21F) that has a crush on me, but I don't have the same feelings for her. Thing is, I am interested in someone else (22F) and I am having sex with this person. We are having problems though.

I have a very high libido and I have been thinking a lot on polyamory relations. I have been thinking of trying to make this girl, that has a crush on me, my fuckbuddy just because i "need" sex on such a frequent level and with the unstable relationship i have with the other girl (22F). 

When I say "need", I don't mean that I am addicted, I just prefer doing it with someone else than using my hand.

I don't want to hurt this girls feelings or make her feel used. Should I just tell her what I want or should I just go for it? The girl that I am already having relations with is not a factor in this decision.

I realize I may come off as a douchebag, but it's really not the case. I really care about this girls feelings and I don't want to hurt them.

Suggestions?

Give me a shortened version of the text
<bot>: Girl has a crush on me. I am not interested in the same way. Is it ok to make her my fuckbuddy even though she has feeling for me?