@abigail-dantes, wow... tough one. I believe, in some cases, depression can last for years, not necessarily because it's clinical... rather because the perspective about one's future needs to be adjusted.
Years ago, I went through a phase where I picked up the bad habit of complaining. I was surrounded by complainers and joined the pity party. In reality, life was actually really good. I seriously don't know how anyone could stand being around me. Then the paradigm shift... I realized I had the power to choose my thoughts... and that my thoughts had the power to define my future.
Ironically, it was after "the dark days", that I truly went through several difficult situations... situations that would have crippled me emotionally in the past... with optimism... with the expectation of love, adventure, and a bright future.
Ha! The brain-mind assumption :)
I hope everyone here gets to read this comment. It is truly insightful.
Thank you for highlighting this points here through your personal experience!
Lots of love to you my dear.
:*
well said