Part of therapy when you have DID is learning the alters and host share one body. my alters didnt have their own separate physical bodys. the alters lived inside my body and shared my body with me.

since its one body, no matter who is in control when the abuse is happening its still the same physical body getting abused.

you and Katrina share your body.
since its one body what is happening to the body happens to everyone in the body physically.

she is probably preparing you for co consciousness. when I started being co conscious with some of my alters the fact that it was one body getting hurt all the time came through very clearly because I felt the pain and emotions of the alters and what happened when they were in control of the body.

If you dont accept that its one physical body so what happens when you are in control happens to everyone in the body when you start feeling those emotions and pain that katrina shares with you when you develop co consciousness of those memories there will be so much more confusion, fear and it could affect everyone that shares your body.

by accepting its one body so what physically happens happens to all when that moment of shared memories and emotions happen you are better prepared to understanding whats going on and get through that moment better.

you dont have to do the excepting of what happened to your phyisical body also happened to katrina cause its one body and what happened to katrina happened to you because its one physical body shared by both of you, all at once.

you can take your time and pick something small that you and katrina have in common and work your way up.