I am not feeling to well.. so please forgive me if I goof.. and say something that unintentially hurts.. would never want too..but wanted to respond...

First I would say.. if you feel you need to be hospitalized to be safe.. then that is what I would do....

It sounds like what you are going thru is just terrible...the trigger.. and the flood of memories.. and the "leaving" of my body, followed by not sleeping.. I have all of that.. though my DX is DID, PTSD and anxiety and depression... so I am not sure what causes this if it is the DID or the PTSD...
I do know it is very hard to experience..

I would ask if you have a T to help...

And.. "hug a tree"... not sure if your friend meant this as a "grounding" tech.. or what....

For me... when this happens.. I talk to my T - he gives me more than one session a week, call my pdoc to see him, and use self "grounding"... I have meds to sleep.. that is very important.. the less sleep the worse, then from there I develop a routine.. it gets life going again, then such things as watching a favorite familiar movie, cooking, rocking, wrapping up in a blanket, heating pad,, soothing things..

But the more you don't sleep... the more "unreal" you will feel.. like a cycle...

(((((safe hugs))))