Welcome to our forum.
There's a lot of good information here; you might find the Golden Nuggets board
You are just starting out in a new relationship style, so it's to be expected that things will be a little rocky. You just have to learn a little at a time, and things will slowly get easier. You and your husband have weathered a lot of things together; you can get through this also.
If you can find a poly-friendly counselor in your area, that might be something to consider (for help with insecurities and to help him become a better listener).
Let us know if you have any questions.