High school was good for me. College was tougher.

I knew college was supposed to get me ready for a life out in the real world but I could not forsee what kind of life I could sustain. All the conventional options didn't appeal. This caused me a lot of distress.

Also I let an unhealthy relationship with a codependent istj (now my exwife) take up far too much of my time and energy.

These two stressors along with chronic understimulation due to wasting a lot of time sitting around smoking weed led to depression.

I'd say things started looking up for me around age 24 when I got a handle on a realistic career path and started making my emotional health a priority.

Edit: burymecloser, well said.