I really dont know what to do anymore..I have this friend and I really care about her but sometimes i just want to yell at her and tell her to stop whining and do something but I know it wont do any good and it would prolly cause problems.

I am not going to go into it but basically he is leaving her at home while she takes of the kids, sometimes he will cause a fight to go out with friends and she doesnt know where he is at all. The other day he was suppose to go to his sisters house and never came home and didnt call her I dont know when he came home i talked to her yesterday before he did and she was suppose to go to my little sisters birthday party but when I went to call her, she didnt answer and then the second time i called her phone kept going to voicemail, so either she decided to turn her phone off or he took it and told her she couldnt leave the house with the kids, idk she hasnt called me prolly cause she thinks im mad which i am a little. Its not about her not showing up, but she could of atleast told me and I am so tired of hearing how she never gets to go anywhere and nobody invites her anywhere and when I do, she doesnt come and go or whatever. I dont know what to do anymore. I have told her a million times if she wants things to get better in her relationship she needs to stop being his door mat. I honest dont think he loves her, and that he used her the whole time and that he only is there because he has it made there, she cooks, cleans, does his laundry, and takes care of the kids, even his nephew and niece. I know she is asking for this shit but she is always complaining making status about how she feels useless and such but yet she wont do anything to change things. I am to the point where I am not going to talk to her anymore about because its not like its going to do any good. I just dont know what to do anymore. I feel sorry for her but honestly if she wont do anything to make things different what can I say to her anymore?? I mean if she doesnt want to be controlled and she continues to allow it what can you say to a person like that? I mean why continue to go through it when you get treated like shit. I also have a boyfriend and we have our problems but not like this. He works and doesnt treat me like shit or anything like that. He can be an ass but in the six years we have been together not once has he made me feel like im his door mat. I just dont know what to do anymore. She is my bestfriend and I dont want to lose her but I also cant stand back and watch this shit. Its messed up.