Massive crush on female best friend [23/f] and confused

Hello all throwaway of course,

I [23/f] have an insane crush on one of my best friends. [23/f] I have never identified as being bisexual or gay. All my previous relationships have been with males. In the past couple of months this friend and I have become increasingly closer and have hung out a lot more than we ever have even though we've known each other for around 10 years. I'm not dealing very well with it emotionally. I get jealous when she hangs out with other people on the weekend which in turn causes fights between us cause I just turn into a complete dick. She probably is completely confused by my reactions. I know this is pretty immature and I'm not one to usually be so petty it's just feelings I can't help...

I've tried avoiding her, not texting back. Tried to separate myself from situations where we have to see each other. Buts it's impossible, we're in the same friendship group we see each other multiple times a week, and when we're not together we are constantly texting . I really have no idea how to stop these feelings that have been going on for months and it's emotionally draining. I have no idea how she would react if I were to tell her.

Tl;dr obsessed with best friend and it's not healthy