I rarely dissociate (I'm all too present most of the time, including during traumatic events). But last fall I spectacularly dissociated twice - as in, "came to" somewhere I didn't remember having driven to, and another time lost 48 hours of my life, during which I carried on as normal - went to work, made phone calls, wrote emails - but remember none of it.

I understand the concern - it's a protective mechanism, but it can a) keep you from dealing with your real life and problems, and b) actually cause harm to you if you're doing things in a sort of zombie way.