I'm the "straight" girl in love with my "straight" bff

so there's this girl i met at school who is not out about her sexuality but I am 90% sure she is into girls. I never knew I could be into girls until I met her. The past 8 months we became close and pretty soon after I started hanging out with her, I realized I am totally attracted to her and want to be more than just friends. We are always really flirty with each other and it feels different and amazing and when I'm with her, I'm on cloud 9. However, she tends to have her guard up a lot and deflects public affection. There is so much sexual tension between us but neither one of us addresses it (but last night at a party we went into another room and we were holding hands for 5 minutes and we can be really cute at times) . I feel like its so obvious we like each other it's just a matter of having a discussion about it. Also, we are both going to college in a few months and I am terrified of bringing it up to her because it could ruin our friendship. I just have such an overwhelming desire to tell her because I don't know if she knows I like her (because I have hooked up with guys and my gayness isn't as obvious as hers) but also because I have such strong feelings. ugh when do you guys think i should have this conversation with her? /should i have this conversation with her? what do i say so that she doesn't shut down? what if she doesn't like me back?

 

thank you, that's good advice. Do you think its too risky telling her my feelings for her now in hopes of having a relationship with her? I say this because it's gotten to the point where I want more from our relationship than just a platonic friendship. I am almost certain she likes me back but I don't know if shes ready for a relationship or wants one. I'm certainly not ready for an open/public relationship, but if we kept it on the dL it could work.