I am madly in love with my teacher

I've been in love with my English teacher for over a year. I got in trouble just because I told a friend I wish I could go to prom with him, then a lot people knew that I had a crush on him, and ridiculous rumors of our "relationship" got spread out. I was actually not aware of the leakage of my secret, so I was shocked when deans and counselors came to me. They said they would have to fire him if conditions turned worse. Though they said they would try not to let him know if those rumors were not true, but I knew that he must know something about it already. I was so scared and was thinking about avoiding talking to him or even seeing him, and actually I was rather upset because I thought he must be mad at me. To my surprise, he was still quite nice to me just like nothing had happened, so I supposed that he was not aware of the rumors and all my crazy feelings about him. I did not doubt that he became over professional when he talked to me was just my illusion until once I overheard he talked about that he was warned not to meet female student alone. I highly doubt a relationship between us would be progressed not only because he is my teacher, he has a girlfriend and he is 17 years older than me, but he might never feels anything about me though he likes me as a student. I am not waiting for a relationship but I just can't stop being crazy about him. I really want to end this because I sometimes feel I've gone insane. I stalk his car; I check my email more than one hundred times a day just to see if there is one from him; I use my phone to make records whenever I talk to him so I can listen to them over and over again; I have drawn more than 20 pictures of him even though he is just aware of 2; I never look at any of the boys in my age because I am thinking about him all the time; he almost appears in my dream every night; I would be extremely nice to those guys who just have the same first or last name as him; I can recite every email or text he sent to me . . . so I think it would be wise for me to stop all those creepy behaviors. But in the other hand, I really want to know what does he think about me. As I am graduating and leaving, everytime I see him might be the last chance we see each other. I always want to tell him my feelings before I leave. I don't care if he knows about it already I just want to say something to him face to face at least once. I was about to tell him for several times, but I did not because I am not sure if it would destroy anything if I actually do it. Can I do it or should I keep the secret? And how can I stop doing all those things when I realize I really cannot stop loving him?