I agree that most people have much to be grateful for. I do.
The thing is that if a person has clinical depression, motivation can be zero. I hadn't thought of it when I first posted above, but if the unhappiness and lack of motivation keeps up then a trip to the doctor might be a good idea.
There could be physical reasons why you don't feel happy, or there could be clinical depression.
Counting ones blessing is always a good idea, but sometimes it's not enough to pull a person out of a slump.