Not terribly responsible of her to jump from dissociation to DID and scare you that way. That's pretty much jumping from A to Z. Dissociation happens on a continuum, from realizing you've driven down the road a few miles with no memory of those miles (everyone does that and it isn't "pathological") to the other end which is DID.

Most of us with trauma backgrounds, particularly with PTSD diagnoses dissociate at certain points. For me it was a sort of zoning away into another place, often with no feeling/awareness at all. Dissociation was how I coped with the abuse when I was very young. I literally see my memories in 3rd person, often from a ceiling viewpoint. I do not have DID, but there were certainly times when I felt very young and got "lost" in those memories.

As I became more aware of my dissociation, therapists were able to help me learn the signs that I was headed in that direction, teach me ways to stay grounded so I didn't dissociate as often or as "far", and get to the point now that it almost never happens anymore.