As if I didn't have enough to do..

I live in Arizona and my husband currently lives in San Diego. Since he will be getting out of the military soon we decided to buy a house and get the kids & I settled where we plan to live forever. He comes to visit almost every weekend--6 hours each way--& I appreciate his sacrifice so much!! However, he left on Valentine's Day for a 3 1/2 month deployment.
As you can see this leaves me with taking care of three children, a new house, cooking, cleaning, etc, etc..ALL BY MYSELF!! It can be very stressful, but I am trying to make the best of it.
I am also in college and I am in my last pre-requisite before I can apply to nursing school! (a goal I have been trying to achieve for the last 4 years!)
I also have a job--after 10 years of being a stay at home mom--and am loving it!! Possibly because I work in a great atmosphere (hospital) with great people (nurses) and have great hours (4 to 12hours/wk)!

BUT..for me, this is not enough! I have decided (with a little nudge from my sister) to run a 1/2 marathon in November!!

What am I thinking??
My down-time is so special to me and now I will have to RUN during it??
*sigh*
I am scared, I am nervous, but I am also super excited. & Would not be able to do it without my sister. I have already started tracking my eating with myfitnesspal.com and I already do work out 2-3 times a week doing Jazzercise. I ran a 5K 2 years ago, but honestly have not done much running since. I am going to set up a schedule and start slowly, but I know I have to start soon! November will sneak up on me, you know how Christmas comes out of nowhere every year!!
Maybe I am hoping if I add enough to my life I can't help but get organized. It hasn't worked yet....