I'm going to hook up with a girl when me and my girlfriend were on a break
Are you going to tell your girlfriend?
Yes, I'm going to tell her about it.
If you are on a break you don't have to be committed. Just make sure you are honest about it.
I'm doing this because she is over us.
Well, as long as the two of you are honest with each other, than  I think no one will get hurt.