What Now?

I have this problem. Well, it is so small that I can think you will only laugh at it. It is the usual teeners problem. I had this friend of mine, Lein. She was smart, the problem is, she is not that good-looking. Then, she has a long-time crush named Morty. He is really cute and thing is, he is our classmate in Mathematics. Now, I thought he was just a friend to me after many years. But then, one day, I just woke up feeling something for him. I am not sure if he likes me or not. He is some sort of a hottie and we are just friends, but we are really close although he has a girlfriend. His girlfriend was the typical girlfriend of a hottie- also a hottie. But then, he always mentions to me that if he and his girlfriend Anne would break-up, I am his next choice. But he says it in a kidding tone.But I also think that he really means it? Whatever. The real problem now is, can i keep crushing on him and liking him when I know that my friend likes him too?