If I were you, I'd just go visit the in-laws during the "compulsory" and necessary days like once a week and the holidays etc. For those few hours, if they are horrible to me, I'll take it as best as I can but if they are mean to my kids, I'll tell my husband to talk to his parents.
My mom went through the same experience with my paternal side of the family because she is a working mom who brought us up to be moderate instead of religious. Whenever they made snide comments about her or any of us kids, she just smiled it off and told us to do well in our education and lives to prove them wrong.
Hang in there mommy!
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