I had those problems back in my school days. The best way of dealing with such problems was for me to avoid my "crush" and try to forget about them. Heck, it wasn't my fault for falling for them in the first place.

Besides, when you stop and take a look at the type of person you've developed a crush on, you start to realise how horrible and pathetic their personality is. If that isn't the case, focus on the negatives and force yourself to dislike them.

Works for me. =/