They were pretty serious, and from what he's told me, she was a mess when they broke up. She messaged him all the time about why he was breaking up with her, telling him that he was the only dependable thing in her life because of her bad relationship with her parents, begging him to take her back, and that she will wait for him forever. She talks about being depressed, having nightmares, etc. to him all the time.
He doesn't talk to her much anymore, just responds when she seems really emotional and sad.
I know I should be okay with the fact that he is helping her through her tough situation, but it also makes me jealous. Any advice on what to do about it?