You'll probably laugh and think "typical teenager" for acting like this is a big deal, but thanks anyway for reading. Here it goes.

So there is this girl I met through my biology course at school, who I'll call E. One thing turns to another and E and I are talking or texting with each other almost every day, and as summer rolls around we are texting each other more than any other people. Over time, I start to develop feelings for E, to the point where I can almost think of nothing else. This has been going on for about 6-7 months. The problem for me is that E has lots of really good friends who are also guys and whom she talks to frequently. I do know for a fact that she talks to me most though, if that matters. E hears from a mutual friend that I have a crush on someone, but does not know specifically who it is, and is now eager to know who it is, and has asked me a few times. Conveniently for her, I lost a bet with her in which the terms were the loser needs to give an answer to ANY one question asked. You can probably see where this is going. I don't know whether to admit my feelings, because if it does not go both ways I don't want this friendship to be ruined. What should I do?