It's not just honey and it's not just honeybees. Whatever is causing this, and it might be ourselves spraying this and that on the crops to reduce crop pests, many of the insects that do similar work are also down. GM crops might also have something to do with it.
GM crops are often engineered to have internal pesticides.
The corporate farms here spray large amounts of pesticides and weed killers. No till farming came and we see no more ringneck pheasants and other birds. We used to have them all over the place. No more. I leave a large section of our field uncut and natural for wildlife. I would buy a few birds and set them out to breed and nest but I am sure they would not do well with the foamy poisons being sprayed on all sides of us.
I would suspect GM crops also -- the tinkering they do to those would also probably cause fatal tinkering with the DNA/genes of bees also. It remains to be seen what the tinkering will do to humans.