P90X: Round Two

And by round two, I don't mean I've already finished the 90 day program and I'm coming back for 90 more days. I mean I'm trying to finish a full 90 days. I completed two full weeks back when I started, but then life happened, and I got behind on my workouts and just quit. You have a specific workout for six days and then rest on the seventh, but if something would come up I would just double up workouts. Then I got a few days behind and there was no way I was going to be able to do four P90X workouts in a day, and I just gave up on it. This time around I just have to make time for it. Whether that means getting up before work, or suffering through a workout after...NO EXCUSES. This time I plan on at least making it until we leave for spring training, and then I can start running again. I'll be bringing the dvds just in case I feel motivated to continue the program, so be prepared Lisa. I'll even bring along my extra yoga mat :)
I'm excited to get to spring training because all of the girls are so motivating. Everyone's in such great shape, many of them are personal trainers and very into working out. When Lisa and I lived together last spring training, she always made me get out and run. She was an athlete in college and still has that drive I guess. I just don't have it. I want to have it, and once I get started I can motivate myself, but this cold weather really makes it hard for me to get motivated. What are y'alls motivations for working out?
I really, really want to run a marathon one day, and I'm definitely thinking the sooner the better. I mean, I'm not getting any younger. But when I'm running I always get to the 2 or 3 mile mark and just bottom out. What are your motivations to get past that slump, to add more reps, or more weight, or add distance, etc? I don't know what to tell myself to get past it. Any suggestions would be greatly appreciated!