My wife has been acting kinda weird lately?

My wife and I have know each other since we were 2 years old. We have always been absolute best friends threw out life. When I was 15 I fell in love with her and we've been together ever since. We got married when we I was 19, she was 20. We're 27, and 28 now, and had a little girl last year. I adore my wife, I cant live without her, we do everything together. And we're a very affectionate couple. But, lately she's been rather dis tent to me. And I know she takes care of the baby and works around the house, she's very busy. And I understand we're both still new parents, and it can be stressful sometimes. But, something seems off. When get in bed together at night, she just turns her back to me and goes to sleep, when we have always kinda snuggled before falling asleep. She's not as talkative, we don't have near as much as we used to have, which I have no problem with, I completely understand that shes tired. But still. We recently moved to Houston for my job, and maybe she misses her parents and sister. I try to cheer her up but nothing is working. Whats going on? Is she homesick, does it have anything to do with me? I try to be the sweetest husband in the world to her always. What is it?