Someone here posted that her counselor told her that what was happening between her SD and DH was now called emotional incest. With that, I thought I'd find a book to read. Oh my, what an eye opener! If there was one book I wish I would have read years ago, it was probably this. It explains so clearly what my DH and his daughter had, thankfully because of the chaos has now been broken, but I am making him read it too! I have to say I even see my sister in this book and feel so sorry for her. The fact is, that maybe you can read this and let your DHs know so they can see the actual damage they are indeed doing especially to these daughters who are treated as the lover or spouse.

Here it is The Emotional Incest Syndrome: What to do When a Parent's Love Rules Your Life