Through my garden the Satan walked, deadly sad

Depression is a terrible, deadly disease. What makes it worse is that often it's not visible on the outside. Most people I meet see me as a cheerful, nice guy, even happy, while at the same time, I'm contemplating whether to end it all today or tomorrow. And how to do it.

"Through my garden the Satan walked, deadly sad
And turned it into a scary, horrible hermitage…
He walked with morose head laid down on his chest
And buried the blooming flowers with ash,
Covered the lawns with the blocks of stone he threw
And sowed the craze of dread and the death of terror…
Until, frightened with his work, [as if] burdened with lead
He lay down in this stone wilderness
To smother the despairs sobbing in his chest,
And the cries with the fiery tears of horrible sorrows…"
 

Statistically, everyone has such a person in their environment. Sometimes, the behavior of that person contradicts the image of depression. I myself sometimes escape from what I feel through various frantic activities (yes, including online activities) or react terribly aggressively in stressful situations.
There's also alcohol and drugs, as well as various compulsive behaviors, acting out, releasing tension. At the age of 17, I started drinking vodka to numb myself because it was the only thing that brought relief back then. Self-harm, risky behaviors (my favorite at that age was running in front of moving cars).
Recently, from someone to whom I inadvertently wrote about what has been happening to me lately, I received a response saying that I'm a 16-year-old little shit, not a man. I've gotten somewhat used to such reactions. Someone else was terribly offended when I pointed out to them in a disdainful manner, "What about you? Depressed again since morning and can't get out of bed?" Such behavior is morally equivalent to kicking someone who is already lying on the ground and doesn't even have the strength to defend themselves, in terms of the damage and suffering it causes.
The past few days have been particularly difficult. It hasn't been this bad in a long time. For the first time in years, I started cutting myself (I used to do it frequently in my youth, both of my hands were scarred), I would start crying while watching some suspenseful TV show because a certain scene or word would trigger something within me, I would wait all day for the day to end, for it to be late enough so that I could go to sleep (if I manage to fall asleep) because that's the only thing that brings some relief.
Due to my illness, I've been on the brink of homelessness several times. I've slept in stairwells or in parks before.
Depression is often invisible on the outside, and sometimes the person suffering from it doesn't even realize what is truly happening to them.
The effects are only visible later on. Broken life stories, destroyed families, homelessness, alcoholism, drug addiction, suicides...
Remember this before hastily judging and condemning someone.