When will I start listening to good advice?

What was your finish time at Surf City?

I guess that would help.

1:53:43

Dude, that was smoking fast.  What was your goal time? 

My last half mary I set a goal of sub 2 hrs and missed it by about 3 min and change.  Like you it was around mile 9 or 10 that I knew that was all I had in the tank with screaming hamstings to feet. 

Sometimes it's the runner going out too hard, sometimes it's external conditions.  The race I reference I was told weather would normally be mid 40-50 degree for.  It wasn't .....it was a bit colder and it was on an island, I hadn't factored in the winds coming off the ocean. (not a local race for me)

Starving when I wrote this so my thoughts are really disjointed.  My goal was 1:52.  My previous PR last month at So Cal 1/2 was 1:54:42.  

I've been running somewhere between 20-25/30 miles a week.  All pretty easy, some hills here and there.  Usually around 9:30 pace for my training runs, ave HR 146 -ish.

I was pretty much at 8:23 average splits all the way up to 8.  At 9 and 10 it dropped to about 8:50, 11-12 about 9:20, 13 8:54.

Also my HR stayed steady about 172 from mile 5-13 with a slight drop at mile 12.

Many years ago I read this (in reference to marathons):

If you go out fast, as you inevitably will, you will finish slow.
If you go out slow, as you know you should, you will finish slower.

At 25 miles per week you may just not have enough miles in your legs to prepare you for a continuous 13.1 miles at race pace.  Doubtful it's nutrition or hydration as long as you are drinking some gatorade from the aid stations and it wasn't extremely hot.  Your pace was consistent for the majority of the race then started to slow at the end... that happens with a lot of people, even more so if your training is on the lower mileage side.