I am sorry that your husband does not understand. A year or so ago, my ex husband went through a depression, blamed the marriage etc and eventually left. I did not understand. We are no longer married obviously which is something I have been dealing with. Anyway, there is a book called "Depression Fallout" by Anne Sheffield which is a great book for someone who is dealing with another loved ones depression and its effects on their relationship. She also has a website. www.Depressionfallout.com
I think going with you to therapy is a great idea, but sometimes they are not open to it. My ex was not. But maybe reading this book or visiting the website will help him understand the disease a bit better. It helped me.