Maybe it is the sunny day, maybe it's because the increase in the anti-depressants is beginning to kick in, but this morning, thank God, I'm feeling much better. I've had a couple of false dawns already, so I'm not counting chickens, but it's so good to feel able and motivated to actually do something without forcing myself to! Still a bit tired, but I'll get there I'm sure! There is a bit of light at the end of the tunnel. For a whole two hours I've actually felt good about myself!
Below is a helpful wee diagram that has helped me understand what's been happening. Maybe it will help others understand a bit more. I think that clicking on the diagram, and then clicking again on the diagram, with a larger size, makes things a bit clearer!

The_Walrus
I am glad you feel better. Thank Pharmacology, I would have said...