Can I be charged assault for breaking up a fight between my girlfriend and the girl assaulting her. I restrained the girl by holding her arms.

My girlfriend was assaulted in her own house by another girl. I intervened by trying to break up the fight. I managed to get in between them until we all fell on the ground. The girl assaulting my girlfriend ended up beneath me. I tried to restrain her by holding her arms with light force. My girlfriend and her were still able to hit each other a few times though. Since this has happened my girlfriend has pressed assault charges on the girl. In response the girl has pressed charges on me for restraining her.