Withdrawal, struggling with ADLs and an ever decreasing amount of energy are all warning signs for me that my mood is heading south in a big big way, and action is required (action is also near impossible - figures!).
The feeling of it being a downward spiral is bang on. That's exactly what it is. Low energy + don't want to get out of bed anyway = stay in bed, energy continues to drop, mood continues to nose dive.
Stopping that spiral? Identify it's happening (tick!) and decide that my Major Depressive Episodes are something to be avoided at all costs (tick tick).
Breaking the spiral starts with getting out of bed, even when it feels impossible/pointless/hopeless/meaningless etc etc etc.
I stick with my Must Do and Bonus lists of things to do like an obsessive at these times. Eaten brekky? Tick. Evidence that I did something, even if it's pretty much a given, I need to prove to my doubting head that I can at least do the small critical stuff.
It's awful. It feels impossible. But the energy doesn't come back until we start to use it. Even more basic, the mood doesn't stabilise until we start geting out of bed again.
Ifwe had diabetes, it would be insulin every day, no matter how awful, because the alternative is far worse. We have depression - our form of insulin is getting out of bed.
Sounds easy. Feels like it should be easy (Depression Brain can have a field day with that - "I can't even get out of bed, I'm so .....). It's not. It's damn hard. But that's the key to stopping the spiral. You know what it's like at rock bottom, you've caught it in time, and you CAN do this. Know that when you wake up, your brain will flood you with a hundred reasons not to get out of bed, then do it anyway.
Thoughts are with you. Know the Depression demon all too well, and I really hope you beat it before it takes over completely.