How do I get to see the light?

Psa 36:9 You are the source of all life, and because of your light we see the light.

Depression, which is really the ultimate opposite of motivation, is often described as darkness.

I do not claim to be grasping the practical application of this scripture, but there seems to me to be a critical element here in the comments that God is the source of all life, and that we see the light because of His light. It is when our lives are light, that we are motivated. When I feel all strong and motivated, it is the opposite of that dark feeling I have when I am depressed.

How do I allow God's light to shine in me so constantly that I never face the grey dusk of demotivation, or even the deep darkness of depression?

Is the previous verse maybe an introduction that gives me a key?

Psa 36:8 We feast on the abundant food you provide; you let us drink from the river of your goodness.

Herein, it seems lie the secret. To take the time to eat from God's hand and to drink from His river, every day, therein lies a great weapon.