National Alliance on Mental Health (US)

If you live in the US and you don’t know about NAMI yet, I super recommend checking out

NAMI is the National Alliance on Mental Illness, the nation’s largest
grassroots mental health organization dedicated to building better
lives for the millions of Americans affected by mental illness. NAMI
advocates for access to services, treatment, supports and research and
is steadfast in its commitment to raise awareness and build a
community for hope for all of those in need.

I also suggest finding your local NAMI chapter to see what resources are available in your area. I have found them to be very helpful in finding various forms of support.