I had a crush on my boyfriend at the time's best friend
Are you still in love with him?
No, I'm not, but I'm sometimes I'm still afraid that I will be too jealous if he's hanging out with someone else.
While it is okay to develop crushes, they aren't appropriate when they are of a friend of your own boyfriend. It's definitely a form of emotional cheating and can lead to actual physical cheating. If you find yourself developing a crush on someone other than your partner, you should spend more time with your partner and try to work things out rather than dumping him and jumping into another relationship.
I don't want to ignore my feelings. I don't want to be with my current boyfriend anymore.
I think that you are jumping to this too quickly. Talking through this with your boyfriend is the best way to handle it. If you both decided the best decision is to break up, then it is fine.