I think I might be in love with my best friend

Well, might is an understatement.
I have known her for a two years now and we have only grown closer and closer. But things grew more significantly during the last 6 months. We just started talking more and more on calls, for hours or so. And studying together, sharing our ideas and listening to music together and other things. She has helped me a lot without knowing as well. I think she is straight for sure and I am nothing more than just a girl. Uh I really think I might be in love with her. We have different classes now, but I am always excited to see her and I wait for her to come by. But this is where the tricky part comes in, I am so jealous when someone who is not me is around her. I almost thought I was going insane but I can't help it, I am trying. She is so lovable, I am scared that I will lose her. Since she is surrounded by people. I thought I was jealous of her at some point but then even I have various friends, I don't feel this way towards any of them. A friend of mine told me to stay away because he thinks this one is going to hurt me deeply. So I have been trying so for a month, I feel happy whenever I am with her even though i have been trying to keep a distance and a week in I have been fine without her. I have no idea where my feelings lie, since they are nether too strong for me to lose my mind and cry and nor too weak that I could just ignore. I think of us kissing and holding hands but then I feel too guilty. I don't know wether I find her attractive in a physical sense because all I remember is that she makes the ugliest faces which are too adorable to forget. I have no idea where I stand in because I'm too afraid to openly feel what I feel. I do know I am bi but this is so new and I don't know wether I can like my best friend. I can't be obvious since everyone we know knows about us. It's almost burdening at one point. I have been ignoring her out of guilt and I feel bad because she has no idea why, I know she thinks something strange is going on but I don't know if I am ready for her to know of this ever. I just thought of writing this out because I haven't told this someone other than a friend who I don't want to get tired of listening to me. Well here goes an experience! I think I'm set on ruining my life. Since I can not imagine ever hating her and if I do I'm gonna lose it.