<human>: Throwaway for obvious reasons.

My brother and his ex have been separated for a few months. It has not been going well. They were each other's everything, and he's obviously distraught. She broke up with him for stupid reasons that I don't need to go into, completely not his fault at all. Since the breakup, she has been showing herself to be absolutely crazy.

First, she was yelling at him, calling him worthless, wanting to kill him, comparing him to her father that left the family, etc. He has been eating her fake apologies up like candy because he still loves her. 

Well, last night, everything took a much darker turn.

They were at a graduation party. She told him to come to the side, and he did. She then started punching him, kicking him, throwing rocks at him, in full view of everyone there. He did not lay a finger on her, and actually said "You people see this? I'm doing nothing. She's hitting me."

She did this three separate times. I know, I know, but he loves her, so he took the bait three times. I know htat sounds fake, but I swear on my life, it's not. People took pictures, videos, the bruises are there, there were at least 10 witnesses, we have enough evidence to put her away.

But we're choosing not to. In the end, that would ruin her life, and we don't want to do that. She needs psychotic help, and fast. We want to get it to her, without making it look like we're trying to screw her. His entire school is on his side, and that could go very badly for her.

I'm so sorry, but I have no other choice. My brother is my absolute everything. If he hurts himself because of this, I will never get over it.

Does anyone have absolutely any advice they can offer? What is the best way to go about getting her help, and getting my brother over this?

Thanks so much for reading.

Can you succinctly summarize the text in 1-3 sentences?
<bot>: My bro's crazy ex assaulted him last night, we want to get her help instead of putting her in jail, and he's still in love with her for some reason. Please help.