Hello, and welcome to SI, KatyDo.
I'm sorry for the circumstances that brought you here, but I am glad that you found us.
Trust takes a long time to rebuild, and requires consistent actions on the part of your husband. What types of material has he read? One common recommendation is "How to Help Your Spouse Heal From Your Affair" by Linda MacDonald.
Another item that might be helpful for him is a post in the Wayward section of this site, called "Things that every WS needs to know", located here:
If your husband doesn't know about SI, you can always copy the text from that post into a Word document and print it off for him to read.
Another resource for you, that you might find helpful is the Healing Library in the upper left of this screen.
Best of luck to you; I am sure you will find plenty of support here!