Winter Blues OR Estrogen?

Blah is the word I would use to describe my current status. I am constantly feeling blah, and said blah appears to be caused by a lack of accomplishment. I don't feel like I am doing enough. I quit my runs to soon, I don't go to yoga enough, I haven't worked on anything outside of my actual job. There still is a gigantic pile of laundry in the laundry room, and I am slowly running out of underwear. Yet no matter how much I do, I do not feel its enough. How do I resolve this issue? Do I do more? Or do I check my head?
Lets examine yesterday. I went for a walk with the dogs, which I currently feel guilty about since it should've been a run. I only ran for 30 minutes on Saturday, and on a treadmill none the less. I do have a marathon coming up; 102 day and counting. I should be running at least 10 miles each Saturday by now. The longest run of 2012 was a little over 5 miles. Pathetic. PATHETIC! On the other hand my little sister is running 40-50 miles a week. Good for her, but what about me?! I shouldn't even bother going out if its not going to be at least a 5 miles run. Oh and great, my Nike+ app tells me I've actually only ran twice this year, not counting the treadmill thing, so three times. Its January 9th and my mileage is approximately 13. 13! Weak. I needs to get my ass in gear and STAT.
I'm thinking I need to run more than a marathon before the marathon, maybe peak at 28-30 miles about a month before the actual race 1) to give me the confidence to run and B. give myself a month to recover. I lost only a week this year so far, so I guess its not the end of the world. Here's the plan for this week:

Day	Run	Yoga
Monday	5 miles	Power Unplugged
Tuesday	OFF	Power 1 & 2
Wednesday	6 miles	Sweat n Soul
Thursday	6 miles	OFF
Friday	OFF	Core
Saturday	7 miles	Yin Yoga
Sunday	OFF	Power 1&2 + Unplugged