I dealt with episodes of this when I was using MDMA regularly and it's not a problem of like, intellectually dealing with being confronted with how the brain works, because I was fully aware of all this and had no problem conceptualizing what was going on with me abstractly, but derealization and depersonalization is a very strong _feeling_ that is very hard to shake and you can't like rationalize yourself out of it. I think it was easier for me to _handle_, because I knew what it was, but that still didn't make it go away. For me it faded after I gave my brain time to recover -- it took a few months.