Hi CD!
Oh no, sounds like dark thoughts and depression are keeping you in the part of the glass that is half empty. That is a tough row to hoe.
What resources do you have in the mental health community that you are willing to consider?
I am a simple person so a simple tool is what I use for first aid anyway. Breathe naturally and silently count 1 on the inhale, 2 on the exhale, 3 on the inhale, continuing up to 10. Then start at 1 again.
The dark thoughts must have attention to support them. If we disregard them and pay attention to breathing and counting, our awareness goes to them.

CANDC