Toxic divorce

My friend is going through a messy divorce. Her husband is horrible to her but he's a supportive dad to their kids. Her husband says nasty things, yells at her, calls her a bit*h and says she's a terrible mother. The problem is, I agree with him. She told her young daughter that she hates her, that she doesn't want to be her mother anymore and that she's the reason they're getting a divorce. Often, she'll pick them up from school and then ditch them on the way home after they argue. They have to catch public transport home. She's always saying he's a narcissist but I wonder if she's the narcissist. We used to be close but I'm starting to despise her. She thinks I'm on her side but I'm worried for the kids. I'm trying to figure out how to support them. I'm staying on her side so I can stay close to the kids. Is he the asshole or is she?