How can I make my in laws believe that I don't hate them?

From your answer, you have a lot on your mind. Your in-laws have every right to be concerned about their son, and where he stands in their religion. But by you staying home with your puppy only adds to the wedge that has been created. By marrying him, you knew of their commitment to their faith, and the baggage that comes along with marriage. You married him, but you also married his family too. Your in-laws should understand your situation, being 4 hours away and such, but again, as you stay away, they use that as fuel. I am not condoning their behavior, but they are only reacting to you staying away. Also, your in-laws are not dumb. Your husband may tell them that he is still faithful, but they know the truth. This only creates more drama, as your husband doesn't have the courage to tell them the truth. If they didn't have to guess how you two were doing, it would eliminate some of the drama. By you reacting to your sibling-in-laws comments and statements, you may feel justified in staying away, but they obviously don't know you well enough to know that you aren't a controlling wife. But by you staying away, not coming around, not attending the blessing, leads them to believe that you are full of excuses, and the dog is your excuse.