Angry Wife

My lady is 14 weeks pregnant and growing. It's an exciting time but for some reason, she's being really mean and standoffish to me today. I know she's feeling lonely cause I'm a truck driver and rarely home. But I try my best to give her all the attention she needs and all the affection/love I can. 
I want to know have any of your experienced this and if so how do I help her with it. What can I do to make her feel better and get past this ?