[ZenFounder]

I'm a mental health professional (PhD) who works with founders and tech folks.

There's a lot of good content here already.

Strategies to prevent mental health struggles: regular exercise, prioritizing sleep, time with friends, a pet, reasonable nutrition, a life philosophy that includes self compassion, breaks from work as well as time to deep-dive into meaningful work, self-reflective practices (like journaling), having a relationship with a "wise" person (therapist, clergy member, mentor, etc), volunteering or finding a way to make meaningful contributions to other people. Many of the other things people have mentioned.

Strategies to cope with mental health challenges include extra doses of all of the above plus a mental health professional who "gets" you. Who doesn't have an agenda beyond understanding you and supporting you. I admit it can be hard to find the right therapist or physician but it is worth the effort. Most problems do not require medication (bipolar disorder and schizophrenia are notable exceptions- they are almost always treated with medication)

Most HN readers will do well with someone who is tech savvy and has experience working with folks in the tech industry.