Not sure what to do with this feeling, I don't want to ruin this friendship

I don't know what to do anymore. I had a crush on a girl (and still kinda do) but I'm pretty sure she is straight or just doesn't like me like that. And we joke around she says and does stuff sometimes that makes me think she might but I know that girls hold hands all the time and it just means a close friendship. I don't know if I should tell her my feelings or not, because I don't want to loose her as a close friend but I feel like I'm lying to her or something or even the smallest chance that she may like me too. One of her closest friends commented on how she "likes me maybe too much", I don't know if that was just jealousy or something else. I don't have many close friends, and she is one of them. I feel like if we can't be more than friends then for my own sanity not act like that. I feel like I should tell her my feelings because I'm starting to get kinda angry or more like jealous of her close friend and maybe it will make me stop feeling this way. I just can't bring my self to tell her, or admit it to myself.