WARNING MAY CONTAIN SA TRIGGER

That can be part of it. I have had experiences like that. My pdoc wanted to rule out temporal lobe epilepsy first.

Normally when I dissociate I seal myself off from the present. Usually involving sex (i was molested as a child and raped as a teenager) It took 19 years before my brain allowed me to remember the molestation. But a lot of my dissociating results in out of body experiences, where I am hovering and watching myself. Some call it "going to your happy place" where I can basically shut my brain off to prevent myself from experiencing things.

I dissociate when I feel threatened (someone yelling at me, or my therapist trying to dig too deep)

You might want to look into depersonalization/derealization. My pdoc at the hospital told me that being unable to recognize familiar places is part of that experience.