What you are describing is absolutely not “mild depression”. I have seasonal and mild depression and exercising is absolutely a cure-all for me, when winter is running a bit too long i start getting back into running to get out of having to otherwise be on antidepressants seasonally.

My wife, on the other hand, has depression like you describe, and she requires a lot of support to keep her afloat. This article is definitely not talking to target your situation. I am so sorry you have to experience life the way you do, i hope for the treatments and support you find to bring the right balance for you to experience the full breadth of the joys of life