MIL mad because we are moving out?!

So I am currently 36 weeks pregnant (Doctor says I'm further along and could have baby any day) and I've been complaining about being in my in laws house ever since they moved in his sister and THREE kids (ages 2,4,&6) in a 2BR house.. We have a very very small room not enough room for all of our stuff plus a newborn, so we saved up and we just got an apartment.. Thought it would be a happy thing! But my husbands mother is pissed, upset, and won't talk to us because we will no longer be living there.. She doesn't understand why we wanted to move or why we need more space.. I mean really we are having a baby and have no where to put his crib, bassinet, much less his clothes.... What do I do to make this better??