Unfortunately, I've known more than one person who ended their life early. I don't use the term "decided to" in these cases because they were in an altered mental state - one in which rational thought is overwhelmed. If you've suffered from clinical depression, you'll know what I mean.
I know many people dealing with depression, bipolar disorder, obsessive compulsive disorder, and various other mental health issues. It is long past time that we got rid of the stigma surrounding these problems. They are serious medical problems that can't be cured by keeping up a good front, staying "strong", or crying on someone's shoulder.
They need medical attention.
Depression should not be a terminal illness. It doesn't have to be.
I know many people with serious mental health issues - and you know what? So do you...whether you realize it or not.