HELP?! My ex girlfriend is in jail!?

You should do as much as you can..but make sure she knows you're doing it because you care about her a lot and want to be more than friends. just in case cuz she might take it as "just a friend being nice." eventually she'll realize that you've been there all along and this new guy isn't worth it (since you say they fight a lot). she'll come to her senses im sure. just keep being there for her no matter what and always offer support.