I'm in love with someone who isn't my boyfriend
Oh dear, this sounds complicated. Why do you think you're in love with someone other than your boyfriend?
It just happened. I guess it's because I'm crazy.
It's okay to fall in love with other people. You should let your boyfriend know you have feelings for someone else so that your relationship can remain honest.
Who says I have to?
You owe your partner the truth about your feelings. They have a right to move on and be happy if you are not in love anymore.