I have sympathy for the people who lost their jobs, as well as for their families and communities. However, there are better energy sources available right now for power and coal is paying the price.
Natural Gas is what's decreasing coal use.
It's almost as cheap as coal in a combined cycle plant, with about 15% the workers needed. Gas powered plants can be shut off and restarted daily, and reliably. Coal plants can't.
As long as natural gas is cheap it'll continue this way.
I believe Coal will rebound though, Natural Gas costs will go back up. With the reserves of coal the US has , companies will find a way to use it.