As the survivor of 40+ years as a chronic borderline depressive, commend your sage advice to the OP.
Please note that the immediate cause of depression is a hormonal imbalance in the brain. The imbalance occurs when there is a need to slow down bodily functions in order to protect organs from the destructiveness of stress. That occurs naturally in grief. But when we can’t identify the need for such slowing, the brain will try to make up issues. That’s when anger and paranoia can arise. The combination of counseling and medication is the best way to treat these issues.
Be a bit wary of over medicating. Psychotropic drugs take a long time to become effective. And what helps one individual with the same problem may be useless to you. The tendency of some therapists is to pile on the meds. That’s dangerous because they are all metabolized in the liver. At one point I got non viral hepatitis and had to stop all medications instantly. The withdrawal was hellish. Just be careful.
I recommend Andrew Solomon’s book Noonday Demonds. It’s an almanac of depression. It’s ironic but the more you know about your disease the less the chance the cause of your hormone imbalance will remain a mystery.
And remember as all these posts demonstrate, YOU ARE NOT ALONE!
For me it was more difficult to come out as someone with a mental illness than it was to come out as gay.