I DNF Boston one year it was my 8th marathon and third Boston I knew the course had a reasonable buildup and had run all my LR on the course. It was a warm and humid day but nothing exceptional, by Wellesley I knew I was in trouble by the time I got to the firehouse in Newton I had to walk I tried to jog up the hills but couldn't . Then I started to get dizzy and started wobble and people started coming up to me to ask if I was all right. As I went by the medical tent someone came out and tried to convince me to come in. I finally made it to the top of heartbreak where my family was waiting and then I bailed. I really wanted to keep going but was terrified I would pass-out and then all the drama would start. Still don't understand what happened