Dr. Jacqueline B. Sallade offers ideas for maintaining your mental health.
Acknowledged that no one wants to suffer depression. However, in addition to the biochemistry and genetics predisposing one to such illness and aptitude, there is an addictive or habit factor neurologically and behaviorally. That means that people get "stuck" thinking and feeling the same miserable pessimism, shame and gloom, even if they have meds and cognitive tactics which promise hope and would seem to help.
Then, it becomes important to think about secondary gain, or what are the benefits of not breaking out of this unfortunate cycle. First, there's the self-image of failure and dependency. If broken, there's the implied obligation and stress of achieving something meaningful. There's learning or re-learning a better way of feeling and thinking. Memories from when that type of optimism and cheer occured can lead to other memories of when everything crashed and the eventual pain, as with lost love or another traumatic event. Meanwhile, there's the relaxation of doing little, mentally and physically. To some people, and maybe not consciously, there's an anger element, too, which involves making significant others feel helpless, powerless and inadequate to help. Depression can be passive aggression. (No matter what you do or say, you can't help me. See?)
It's harder to face what's gained by staying depressed, anxious or disabled in some way than to face accepting it and adapting often. Whether that's fair or just, it's true. It's hard work to undo damage and takes courage, stamina, forgiveness, love, and will.