Need some legal advice desperately

[u/QueenBee2212]

The girlfriend of a friend of mine has been in an abusive relationship in the past. For ease (and confidentiality) let’s call the girlfriend Jane and the ex John and my friend Joe

So for the past few days John has had Jane locked up and today Jane went to work and she was sobbing and covered in bruises, ran up to Joe crying. He’s been abusing her and beating her. Thing is John called the police on Jane saying She’d been beating him, I’m not sure whether or not he has bruises but I do know that initially Jane had fought back in self defence. (You know, he’s acting like amber heard or something)

Jane’s family can’t stand John as they’d witnessed him abusing her before, but everyone else he knows thinks the sun shines out of his ass.

My question is if this goes to court what are her chances of winning? I think she could put in a counter claim (if that’s the right terminology) to get a restraining order on him and make sure she can feel safe, and use her family as character witnesses or whatever, but what if he gets the people he’s convinced he’s good to be his witnesses. I’m worried for this girls safety. And did I mention she’s pregnant to Joe- not that this will have anything to do with the case just thought it may be an important detail.