I wouldn't be too worried about it falling apart, my only concern, given the number of miles you drive, is that once you pass the 100,000 mile mark (150k in the green states), you won't have any more warranty on the hybrid components.

I think the car itself is pretty solid and will easily make 200,000 miles or more but I'd hate to be unprotected on such expensive components. I think you have a couple options:

1. Plan on selling/trading the vehicle once it is out of warranty.
2. Take the money you are saving in gas (over $1000 a year at $2.5 a gallon and 30 mpg for a FEH) and put it in the bank in case you need major repairs once you are out of warranty. By the time you are out of warranty you could have several thou in the bank.
3. Buy 2 FEH so that you can get more time out of your warranty before you run out of miles. I do close to 30k a year and my wife does less than 5k. I swap back and forth between my two to average out the miles on them. I am hoping my warranty runs out of time about the same time I run out of miles.
4. Look into leasing one with a high mileage allowance.

I think you would be fine with the FEH. Go for it.