I need some opinions on what to do here. I know I can not live with my husband anymore. I feel bad leaving him with nothing but he is VERY sick.

I have been married almost 3 years with him a little over 4 years. Since I've been with him it's been a consint battle between me and his now 12 year old. His other two boys LOVE me one is 14 and the other is 5. I also have a 9 year old and we share a 2 and 3 year old.

Now he's the sick part. His 12 year old is his little princess. If she wants something EVERYTHING else needs to stop in order for him to take care of her. She's always sitting next to him and has to have her nose in everything he does. She's allowed to wear a bra that is a size too big for her. She looks larger in the chest area than she really is, speghetti stap tops with her bra hanging out, tube tops, see thru tops, and the list goes on. He told me when we first started dating that he had his baby girl in his lap and "it felt like having his first high school love in his lap". She doesn't have to do anything around the house, meals are supposed to be planned around what she likes, she doesn't have to shower, brush her teeth, or do any general care when she's here. He's allowing her to run my life. If she has money come up missing he sits everyone down until it's found, if someone is missing money he says "oh well should've kept it up". I have caught her with my money a silver half dollar that is hard to find in her pocket and he says well we can't prove it was hers. I later stole it back. It's a totally sick relationship. I know he suffers from mental disorders but this is beyond what any sort of normal person might do. Please give me some advice. NOTHING I have tried as helped. I am worried for the both of them, as well as the rest of my family.