Annoyed don't know what to do...

Ashley • TRW 💍 Empress ❤ Heiress 💜 Soul 💙

Me and my fiancee have just moved into a nice sized 4 bedroom house, he has 3 kids he might receive custody for from his previous relationship. Before moving in we decided his youngest daughter, 3, would have her own room, his two boys 6, 8 would share a room. we of course would share the master which has a nice sized room attached to it where we would put our upcoming newborn. Now that we are actually in the house he wants us to have a small sized room where we will be basically cramped while all his 3 kids and our newborn share the master. I feel this is such a dumb idea because I was looking forward to having my newborn in the room with me and me and him having a fairly nice sized space of our own. he basically won't let the idea go now and I'm stuck being the asshole who wants my daughter to have her own room like we planned. I have nothing against his kids. he feels it's unfair to his kids if my daughter has her own room. I'm totally frustrated and at this point just want to move out in total. I feel he doesn't want to even compromise and I felt the previous set up was going to be way nicer. I'm so damn annoyed I don't even know how to approach this.