happy#201 – symptom or cause?

Don’t we often mistake the symptoms for the cause?
Somehow this seems to be a a very humanly behavior because we don’t only do it for ourselves.
I have recently been on a road trip through Germany and I was shocked to see how many forests all over the country where dying.

A result of the heat I thought and a research showed that they actually die because of some bugs. 
But the bugs have been there as long as the trees. So this does not have only one cause. Multiple factors of stress add up until they reach a level where the trees can’t cope with it anymore. 
Isn’t that the same in your life? 
Where do you confuse symptom and cause and what can you do to work on the cause so the symptoms disappear?

All the best, Floh