In my case, the longer I am stuck in a treatment-resistant depression, the worse my self-esteem, social anxiety become. i have dealt with this for many, many years (over 30 yrs). It feels like slow and eventual erosion of the core of my Being.
Depression is oppressive, causing contraction, and hypomania is very expansive. We cannot imagine possibilities while in a contracted, bleak state.
Yes, I seem to be missing it, too, whatever it is. Lol.
Is it zest for life, perhaps?

WC