So i've known this girl for like 10 years now, and we have always been best friends. About once a year i start having feelings for her, and they are always super strong, but eventually pass. Recently we have been hanging out a lot, and Im taking her to Junior Prom (shes a senior) I heard she wanted to ask me to her Senior prom, but someone else had already asked me. Usually these feelings for her pass but they are super strong now, and i dont know if they will pass this time. Also recently shes been very flirty and touchy-feely with me, but Im not sure if its just because were really good friends, or because she may have feelings for me also. What should I do? She will be going to college next year. Do I do nothing and hope the feelings pass, not risking our friendship at all, or do i try and make a move or tell her that I like her and risk the friendship?

Wow that is really great advice. Thank you so much!

So recently, I have been more flirty with the girl, and shes not backing off at all, but the question is: is she just not backing off because we have always been super close? or because she doesnt mind it? or because she likes me? We've been hanging out a lot recently, and the more time i spend with her the more i like her. But the more I like her the more confused I become because shes my best friend... Need more help...

Just thought I would provide an update.....
So a week ago, me and her were hanging, and cuddling up, and i was trying to work up the nerve to talk to her about how i felt (I had already done so once, but after a long talk, she asked if we could just decide how to move forwards later). When i was about to finally say something, she leaned forwards and kissed me, and we continued to hook up. For the next hour or so we hooked up, until i walked her to her car, and we stood under the stars continuing to hook up. The next night she came over again, with similar results. So finally last night we were hanging again, and this time as we were hooking up we got really into it. After a couple of hours of this we cuddled for a little bit. I told her that I really liked her, to which she responded, "I should tell you that the first time we hooked up, I didnt really like you, but now I do." Supposedly I changed a little, but honestly I dont care, so long as she likes me now. She then continued to ask, what "this" was. I told her i wasnt sure but that Im up for anything, either causal or a relationship, and that it is up to her because shes leaving in 3 months for a summer semester at college (shes a senior). Now heres the problem, the more I think about it, the more I start wishing I had told her i wanted a relationship. I feel like i should give these last 3 months everything I got and if were in a casual relationship i dont know if i would feel right "giving it my all." Should i tell her i want a relationship? Or do i leave the decision up to her?