Hmm. I *think* the positivity we feel when manic or hypo is not quite based in reality, I don't know how to say it. More like magical thinking than intentional thinking.
When that is happening we are still not the ones directing the thoughts rather the thoughts still directing us. Does that make sense?
What if you change your routine a bit and not check FB for a while hard as that might be. Sounds like it is creating a compare and contrast thing that doesn't seem to be helping.
I'm not sure if you use mindfulness Purple, but that has really helped me when I am stuck on my perception, and working with depression, stress, anxiety. Jon Kabot Zinn has some really good videos on youtube. When I feel myself slipping I will watch one or a few to help get myself sorted and back on track. Maybe that might help you too?
Edit: sorry I disn't see the please dont tell you to not visit FB. I must have been typing when you replied.