Love to Travel/Terrified to Fly

I absolutely love to travel, but I have such a fear of flying. And honestly, its worse right before I get on the plane. I am flying in about 7 hours and for the last 12+ I have been a wreck. Everything sends me off down a spiral. My dog sits on my lap and I think she "knows" I am never coming home. My kid goes to bed and I cry because I may never see him again. WHY??? What is wrong with me???