My friend hits her boyfriend. What should I do?

Anonymous

My parents say it's none of my business, but I feel like I should at least tell someone? My friend/roommate beats-up her boyfriend when they fight, and they fight often. She punches him in the face and keeps hitting or smacking him even when he says "stop hitting me". I'm one of the only people who've witnessed it since they usually do it in their room but occasionally in public. I asked my friend about why they're so bad with each other and she says it's because "he gets on her nerves." She also stalks his location if he breaks up with her and goes to the location to coerce him back into the relationship. She threw his phone on the ground in anger and it smashed.

Is it my business? Should I tell someone or talk to my friend and say something different? She is my friend but I'm not close to him. But I worry about them and care about both of them. I do worry someone's going to go too far and end up dead one day.

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Should I talk to her? What should I say?
My friend hits her boyfriend. What should I do?
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