"This too is a grievous evil:
As a man comes, so he departs,
and what does he gain,
since he toils for the wind?
All his days he eats in darkness,
with great frustration, affliction and anger.
Then I realized that it is good and proper for a man to eat and drink, and to find satisfaction in his toilsome labor under the sun during the few days of life God has given him-for this is his lot. Moreover, when God gives any man wealth and possessions, and enables him to enjoy them, to accept his lot and be happy in his work-this is a gift of God. He seldom reflects on the days of his life, because God keeps him occupied with gladness of heart."
Our perspective on our situation can vary greatly. We are made up of our childhoods, personality and our experiences and you could have ten people view the same situation and come up with ten different stories of what happened. We should appreciate what we have in life whether a lot or a little. If we focus on the giver (God) instead of the gifts then we will be able to thrive in our lives and practice our gifts with purpose.
There are many that live in the past. I was one of them. Always remembering and not really living in the present. We can't hold onto the things that happened in the past. It's as if they are mist in the shadows, we are never able to grasp those memories and live in them again. Many waste away from putting all their efforts into looking back. So here it says that when God give us wealth (this does not necessarily mean money) He enables us to enjoy what we are given so that means we should only seldom look into the past. We should be joyful, but often we decide we do not want to stay in the present and go into darkness that is a long and lonely road. If you are constantly looking in the rear view mirror you will miss where you are going and all the people along the way.