I want to plead to your spiritual side on this topic, because you brought up church group. And let me say how my heart breaks for your predicament. I can't even imagine.
You carry a lot of hurt, resentment, maybe bitterness, and most definitely anger. Its a perfect response anyone would have in light of what has befallen you by your husband. Your husband is wrong for his actions and he will have to answer to a Higher power as a result. Just as your husband will have to answer for his wrongful and hurtful actions, you will also have to answer for your heart and mind.
I firmly and adamantly believe that giving yourself the opportunity to be resentful, bitter, and angry with your husband will hurt the very person you are. You are a loving and loyal wife and a responsible mother. And God is well pleased in you for this! Don't let the enemy rob you of your identity! And don't give in to the hatred the enemy would want you to have.
The HARDEST, yet best cure for you, is to forgive. You cannot start healing until you start forgiving! I promise you this! And when you forgive (truly forgive), I guarantee you that you will see things in a whole new light and understanding. You will not understand what I am saying until you commit to forgiving. "But he did the wrong. He hurt me." You might say. And you are right...you have been hurt and you are hurting and God knows this, but God cannot do any healing within you, until you first forgive. I implore you and utterly encourage you to take every thought captive and not give the enemy a place in your head to think ill-will and hateful towards your husband...forgive and watch how the Lord will intercede in and through you.
I will be praying for you.