Livid with my husband

Our daughter is going to be 3 months on the 17th and I have been so proud of myself for breastfeeding and sticking with it even though it's been hard. Well today was my first day back at work I sent 7 4 oz bags of milk with her to much mother in laws. I leave for work before my husband so he drops her off and has her for an hour while I'm gone. He just told me he didn't want to use my milk that I was sending so he gave her formula! I'm literally sobbing over it I worked so hard to get that milk that's what it's for and he is mad at me because he doesn't understand what the big deal it.