If I am trying to justify a behaviour, does that not imply that I know it is harmful, and am trying to find a way to make it acceptable? This in turn assumes that I am aware of what I am doing and how it affects those around me. If somone is truly acting without this awareness, I think they cannot be faulted.

I personally did not know for a long time that some of my dissociated states ammounted to an emotional disappearing act that triggered everything from fear to rage in those affected. Once made aware of that fact, I was open to hearing what would mimimize the impact of what is largely a choiceless process for me. Over time I have become somewhat more able to identify these dissociated staes within myself, and can then at least name for others what is going on, as a means of reassuring them that they are not crazy or have done nothing wrong.
The next step is learning the things that will ease me back into 'association' if you will. If I lived on a desert island, there would be no impetus to do so, but to the extent that I am affecting others, I need to be willing to work on this stuff. This is about taking responsibility for my every action in this life.

Anyone who attempts to absolve me of that reponsibility by justifying bad behaviour is doing me and themselves a great disservice.