Brain Sludge!

It's been a few weeks, ya'll. A few tiring, sluggish, busy weeks.
My body just didn't want to work with me, and my mind didn't want to tackle the hard workouts that were coming up in my 10k program.

My previous workout of Walk 5 mins, Run 25 minutes, Walk 3 minutes, Run 15 minutes, and Walk 5 minutes was apparently just too much. I left the gym that day feeling terrible. I don't know what it was, but it made me take 2 days off before I'd even attempt to think about going to the gym.

Then came the weekend and I procrastinated by trying to teach my dog to roll over (he didn't like the concept). 
I apparently didn't like the concept of trying to hit the gym again to do a full 10k workout, so I compromised. I would go on Saturday AND Sunday, but would do my own workout for a half hour. 
I finally got myself out of the house and my workout looked a little something like this:

Walk 3 minutes 0.0% incline
Run .25 at 5.7 speed 0.0% Incline
Run .25 at 5.7 speed 0.5% Incline
Run .10 at 5.7 speed 1.0% Incline
Run .25 at 5.7 speed 0.5% Incline                 Run .25 at 5.7 speed 0.0% Incline
                                                                      Repeat until time is up.

Then I added about 5 minutes of walking on to the end.  I did about 3 miles on Saturday and 3.3 Miles on Sunday. (Easter dinner was a good motivator to burn more cals!) I found this made the workout go a lot faster by focusing on the little blocks of distance over the bigger block of time. 
When I went back on Tuesday to attempt the big workout I had been avoiding, it didn't turn out to be so bad! I did about 5.10 miles which was mostly running. So I'm getting there...only about 6 more workouts til the 10k program is DUNZO!
Then I have to find some decent balance (strength/cardio) to bring me though 5 months and then I start training for the half marathon in February!

My major problem with running seems to be keeping the momentum going! Every time I stop for any long period of time, I'm just done. I don't start again until I make a big decision to start again (which is usually a year or so after I stop). I just need to wade through all the sludge in my head telling myself that I'm too tired or too worn out to keep going. I know better. I've climbed MOUNTAINS (Plural!) before and didn't die...so I think I can run for an hour on a treadmill.

Focus has to be on the goal. My short term goal when I started was to lose 25 lbs. My long term goal is to run a half marathon.
I'm now down 15 lbs, and have only 10 more to go...and I'm finishing up a 10k program which means I'm about halfway to a half marathon. I just have to keep myself going and can't let myself get complacent. 

Just have to weed through all that yucky negative brain sludge and to focus on the end goal.

That seems to be the bigger problem than the actual running...My mind is a bigger obstacle than that 13.1 miles in front of me.

How do you get over all that brain sludge?
What's your biggest obstacle when trying to reach your goals?