Mother in Law problems

Melisa

Looking for a gauge of how mad we should be. I'm 10 wks 4 days along with our first baby. We told our parents shortly after we found out around week 3-4 but have been waiting to tell family and friends until we clear the first trimester. This past week we were on a trip and my in laws went to a family dinner with my husbands grandparents, aunts/uncles and cousins, 20+ people, where my mother in law told everyone we're pregnant. When we got back from our trip she told us that she told everyone and didnt feel bad about it because "she's so excited!" We are furious but dont know how to proceed. I feel like she took away our great news and broke our trust. Now what?