I totally get this Elizabeth. Personally, I deal with dysthymia (chronic, persistent, low-level depression). The thing about dysthymia is that a person can struggle with it for years. I've basically dealt with it since I was a child. And, like all forms of depression, it's a particularly slippery beast, so if you aren't vigilant, it can develop into a severe level of depression.
As I've been on this journey, I've tried pretty much everything--prayer/meditation, journaling, cognitive retraining, diet/exercise, therapy, and lots of just plain old "gutting it out." All of these worked...until they didn't. I'd always wanted to exhaust every option before taking any meds. Well, I arrived at that point in 2009. When I began taking cymbalta, the effect in my head was so startling I remember thinking to myself, "this much be how the brain of a normal person functions." I took cymbalta for about four years before getting off of it.
Part of what people don't understand is this: Everything I did represented a great level of effort on my part, and significant amounts of self-control. Even while I was depressed, I showed up for work and did my job well, and used all my energy in the process.
Even people who've dealt with significant physical illnesses can understand the difficulty of very simple day-to-day activities. What once took moments and required little energy, might now take all day and demand all we have.
I'm glad to hear that you're working with a therapist as you walk through this time. I pray that you'll get some good skills and insights there, and that even at this very low time you will remember that the Holy Spirit is your advocate and intercedes for you with the Father.