A thought....if the problem is caused from letting ones guard down then wouldnt being diligent / putting your guard back up /going back to using what ever means that you used when you were able to have control fix the situation...

when ever something I have had control over in the past but suddenly goes out of whack my therapist says...

lets look at this for a moment...how did you have control over this dissociative problem in the past? and I would say this is what I have been doing this or that grounding technique. but I stopped doing that..I guess I just let my guard down or I didnt want to continue doing that any more..She would laugh and say in a funny voice over "doctor I hurt when I do this and the doctor says then dont do that." her point was I had caused my own problem by not continuing to follow through with what I know works for that type of problem. By not being diligent in keeping my guard up/doing what ever works against my dissociative problems the problem came back to haunt me.

once I went back to using grounding again the dissociative problem went back to my being able to have control over it again.

since you know what works with this problem just go back to doing what ever worked that gave you control.

my suggestion for seeing the new therapist....consider telling that therapist about your dissociative problems..that new therapist may have some new therapeutic techniques that your post therapist didnt have that may be helpful to you.