I haven't shared this with anyone, but I can't stop thinking about my girlfriend's friends.
That could get you in a lot of trouble. Why?
Because they are so cute and sexy to look at
It's okay to experience attraction, but you shouldn't be preoccupied with other women besides your partner. It's not fair to your partner to be preoccupied with other people.
I can't be with them because my girlfriend will get mad at me
Glad to hear you say that. Focus on the good qualities of your girlfriend and be grateful you're with someone as sexy as she is.