"Situational Depression" may occur when life circumstances cause stress: death, empty nest, job loss, etc. "Clinical Depression" originates in a chemical imbalance of the brain's neurotransmitters (dopamine, serotonin and norepinephrine), without any necessary external trigger.

https://www.mayoclinic.org/diseases-conditions/depression/expert-answers/clinical-depression/faq-20057770

https://www.verywellmind.com/the-chemistry-of-depression-1065137

If you are in acute psychological distress, please contact the national Suicide Hotline at 1-800-273-8255 or NAMI (National Alliance on Mental Illness) at 1-800-950-NAMI.

Thanks for listening!
~ Benjamin