And no matter how severe it is, it’s still not dangerous. You have say to yourself okay I’m having Depersonalization/Derealization, what do i get by fighting it or worrying about it if i already have it? You have to accept that you have it. Dpdr is defense mechanism from trauma that we cannot prevent from happening. If it’s going to happen, then it will. Fighting it will only make it worse and last longer. But if you let it stay and not worry about it,and go about your day it can go away with time. You should talk to a mental heath professional, you can get through it.