joint custody and money problems

Q: I have been divorced for over a year now, and share joint custody of my four teenagers. Aside from losing almost everything in the divorce because I could not afford a lawyer, I am having trouble with disrespectful kids.

My ex gets angry when things don't go his way. My children are beginning to treat me the same way. They get mad at me if I can't do what they want. It usually has to do with money. They never ask their dad for things they need or want, so they ask me, when I say I can't afford it they get mad and make me feel like I'm a bad mom.