First, I am very sorry you are going through this at this time. I think the most important thing is you need to feel comfortable with yourself and what information you feel comfortable sharing either with your therapist or with your husband.
Before you share the information with your husband verbally, maybe writing a letter to him about your feelings or anything you want to tell him. You don't have to give him the letter, it can more be a 'practice' for you on telling your husband. You can destroy the letter after you write it, if you don't want to give it to him. or You can read it to your therapist in a session.
But I defiently think you need to be comfortable in how you approach your husband and what information you feel comfortable sharing.

As for your husband, sometimes people are going to ignore or run away from things they don't understand or know how to handle. This sounds like what your husband is doing. He knows and wants to support you, but is scared because he doesn't know how or what to do.