Am I crazy to want to go back to school?

I am thinking about quitting my job to apply to graduate school. Worse, I am thinking about moving to the school campus 70 miles away and leaving my husband and teenager at home for the 2 1/2 years it will take me to complete the program.I have got to be flippin' NUTS. My devoted husband encouraged and supported me while I went back for my Bachelors degree and I have been in my new profession, sales/transportation, for a year now. After this year, I realize I am not happy. I read up on the Masters of Physician Assistant degree and I think I could be a PA and be happy and fulfilled. I know I can succeed academically and complete the program. But I am a GROWN UP, with a big girl relationship, a house, a brand new car to pay for, and a 15 year old son. The closest program for PA's as I said is 75 miles away. My husband says I can make as much money as a PA in my current job. But I am very self-aware, and I know in my heart I am not going to enjoy sales, like, ever. I'm just going through the motions and getting by day to day. I have always been a person who does what the hell I want to do, and just goes for it. But I have my family to think about. What can I do?