At this point, I think it would be important to find a clinical psychologist who works with teenagers and families. She is going to need emotional support from someone that she trusts outside of the family. A skilled clinical psychologist will be able to establish a relationship with her without pushing her to disclose her feelings before she is ready. Some counselors will rush into confronting emotions before building rapport with their client. As a teenager, you daughter likely feels caught in the middle. Your husband's manipulative behavior is creating what is known as a "triangle" in family therapy. That is, the boundaries between them are becoming diffuse (i.e., loose and too flexible). For example, she should never be sleeping in bed with him. This excessive closeness between them pushes you out of the relationship. Picture a triangle with two points close together that are connected to a third point which is very far away. As they pull together, you become isolated from them both. However, you are still apart of this triangle and are the only one capable of changing the pattern of interaction. You must take steps to separate your daughter from your husband, especially since we are unsure about the possibility of sexual abuse.
In reference to your question about how this process will play out, it seems likely that this relationship between them will become more intense as the divorce plays out. The fact that your husband has no friends outside of his family is unusual. He will likely cling to your daughter and attempt to manipulate her further. As her mother, you have to step in to protect your daughter from him. If you go to see a family therapist, they will tell you that your husband's relationship with your daughter constitutes what is known as "enmeshment" in family systems theory. Enmeshment takes place when normal boundaries between people are crossed. That is, when psychological and emotional boundaries are crossed, which makes it especially difficult for a child to develop healthy emotional attachments. Young women like your daughter usually form extremely strong attachments to boys they date. She may rush into physical relationships and become emotionally attached to men. She is rebelling against you, which is not that unusual for a teenage girl her age. She sees your husband as some sort of heroic figure that can save her from you. This does not mean that you are doing a bad job as a mother. It just means that your husband is manipulating a natural urge for a teenage daughter to break away from her mother. You are not to blame! When you have a "triangle" such as the one that exists in your family, everyone plays a role in its creation. Fortunately, you have the power to break up this pattern of interaction between them. It sounds like your husband has a "dependent personality" and needs to be connected with someone to feel normal. His lack of friends and behavior may indicate the presence of some type of personality disorder; however, I cannot make a diagnosis without meeting him.
BotXXXXX XXXXXne: Even if she gets angry with you...which she likely will...you need to separate her from your husband. You should attempt to get into family therapy (i.e., just you and her). You can explain the situation to the therapist without your daughter in the room, so that the therapist won't be blind to the manipulation taking place. The therapist should be a clinical psychologist if possible. Clinical psychologists have the most advanced level of training in psychotherapy. Let the therapist know that you are concerned about them sleeping together in the same bed. If the therapist finds any more information, this may be grounds for filing a police report. A father figure is important in a young girl's life, but her relationship with your husband is just creating emotional conflict and boundary issues that will persist into adult relationships.
If you found this information helpful, please accept my answer so that I get credit for my work and time. If you have any additional questions, I would be happy to help you. Feel free to ask more questions regarding this issue. You will likely need a great deal of support and encouragement to get you through this very challenging situation. BUT....You are a good and protective mom...you can do it! Your daughter will probably thank you one day...just not today.