Would I be wrong to abandon a friend who's going through a hard time?

One of my good friends is going through it. Her husband cheated on and left her. She had a miscarriage and got trich from her ex. I have been being there for her and she wanted to tag along with me to my brothers 21st birthday. I said okay. My sister couldn't make it but my nephew who's 12 was there. It wasn't like a huge party. There was alcohol but it was just a chill day. My brother doesn't really like alcohol anyway. We watched movies. Played cards against humanity and ate snack. Well my friend ended up getting super drunk. She was stealing people drinks to chug down. Then she got so drunk she stripped down naked and tried to go outside my brother and his friends tried to keep her from doing that. Then she got on the table and in front of my 12 year old nephew spread her legs wide and started masturbating her. I was mortified and thought I gotta get this bitch out of here. I eventually did and took her home. I don't think my nephew told my sister because I would have gotten a call with her ready to murder me and her. She's been calling me and sent me a text saying "Sorry about getting so drunk. I probably should have eaten more. Sorry if I traumatized your nephew🤣🤣🤣." She isn't taken what happened seriously and I've been ignoring her. Like if they report that she would be a sex offender! I kind of want to distance myself from this friendship. I've gotten shit faced and gotten shit faced while going through something and NEVER did that.

Edit: I had forgotten my nephew was even there for a moment. Everything happened fast. One minute she was fine. The next she was naked and running around trying to go outside. It's not something I would have ever expected from her