I think I bonked.
This morning on the way in I got about six miles into the ride and suddenly just felt weak. I got a bit shaky (as happens if I fail to eat for an entire day) and I had no energy whatsoever. I kept going for another mile to reach a park that I pass on my commute, pulled in, drank two small sports drinks and ate what I had packed for lunch. About fifteen minutes later I was OK to continue the commute and actually made up for the time I lost prior to pulling into the park.
Here's the weird thing - I didn't vary my morning routine whatsoever. My diet has remained constant. I usually do not eat breakfast prior to leaving. Generally, I drink a Monster (16 oz.) and some iced tea, or some cranberry juice. Then I do the ride in (20 miles), and when I get to work and I'm cooling down I have some sports drink and eat some trail mix. That's served me well until this morning.
My routine yesterday changed only in that instead of only doing my commute (20 miles in, 20 miles home), I did another 6.5 miles w/ my wife when I got home - but at a very, very easy pace.
Have any of y'all had such a thing happen? How do high mileage commuters handle their dietary habits?