Why is my 13yr old daughter mean to me
	
	
		I am a single mother of two, 13yr old daughter and 11yr old daughter.  My ex and I have 50-50 placement and custody.  Is it normal for my 13yr old to be plain out mean to me when she is with him?  I left her a message on her mySpace just asking how summer school went and what did she get from her father (he told me he got them a big surprise) and she responded, " why do you care." And I have not heard back from her.  Even when I call there to talk to her she is real snippy to me.  When she is home with me she is fine.  I don't get it.  Am I too involved and maybe I need to back off and not talk to her when she is over there?  I am really upset.  What does this behavior mean?