Although we live together and are married but we are not together what authority does the step father have over my children?

My husband and I are legally married. I have 4 older children from a previous marriage and three of them live with us. We also have 4 younger children in common. We are separated by all sense of the word except living in the same home. We have separate bedroom, separate bills we take care of, eat separately most of the time and other than an in-home movie night don't even watch TV together. I have the responsibility of all 7 children discipline where I only allow him to disciple his biological children. We only make mutual decisions together when the common children are involved. With that being said... My 17 year old from the previous marriage made sexual advances towards my husband and he declined. She continued and added untrue information such as I was "sleeping" around. He declined. She continued and eventually he gave in. This information was brought to my attention by her and since he refused to run away with her at 18, she has filed sexual assault case against him. Is there a d