Finnally noticing

So my husband is in the Army and often has to go off for training. Sometimes it's for a few days sometimes for a few weeks. Well he went out for training this last week and it was the first time Riley really noticed him being gone. Every time we would get home she would start saying "dada o, dada o" which means dada home. I would have to tell her "No baby dada isn't home, only a few more night nights and you will get to see daddy." Or she would see someone in uniform and point to them saying "dada dada." It made me so sad. Not really because she is noticing but because he will soon be deploying and she is going to understand that dad isn't there but wont understand why. His return after 4 days has been pretty eventful too. She was excited when he came home but doesn't want him to do anything for her. I've been trying to leave them alone for a bit to let her get used to him again. She cries out for me allot. I feel so awful because I'm sure this hurts my husband, he knows she isn't doing it to hurt him but it still hurts when your child doesn't want you. It's also a preview into what she will be like when he comes back from his deployment. When he leaves she will just have turned 2 and when he returns she will be 3. So he will be missing out on a year of her life, a pretty important year. She will start speaking full sentences, making friends, learning her colors and letters, and many more things. This is a part of the life of a military family. Having to say goodbye for a year at a time, missing out on important milestones, dates and events. I completely understand that this is what I married into but it doesn't make it less hard. Without children I could deal with my missing him, but I don't know how I'm going to deal with Riley missing her daddy, not knowing why he went away and then why he suddenly came back. We will do what we can to keep her close to him, talk on the phone and also on IM with webcam. I am preparing myself, but still not sure how I am going to comfort her or help her to understand.