Just to clarify, and because the point bears reiterating, I do not think that most INFJs doorslam in unhealthy ways.
Nonetheless, I think non-INFJs in general, and ENFP's in particular, have a hard time understanding doorslamming. So please do not confuse non-INFJs struggling with understanding doorslamming (either in a healthy or unhealthy context) as the same as INFJ condemnation.
I think that my pain with unhealthy INFJs did come out in a few of my earlier posts. And, these INFJs were not at their best when they did doorslam me. But I've come to view these as painful, though valuable, learning experiences.
One of the most powerful ways I've grown to understand myself is by understanding my INFJ mirrors. INFJs and ENFPs are such fantastic foils. We have the exact same hierarchy of functions, only the energy direction is reversed.
ENFP — Ne > Fi > Te > Si
INFJ — Ni > Fe > Ti > Se
By better understanding INFJ doorslamming, I have come to know better my own ENFP excesses... such as me not seeking closure in my relationships often enough. I learned that if I let my judgment of people hang open too long, this brings on its own uniquely ENFP hell.
LotsOfHeart was right in saying that there are indeed destructive people out there. Had I sought more of a sense of closure, earlier on in certain of my relationships with unhealthy people, I would have avoided a lot of pain and heartbreak. If only I had kicked these goobers to the curb earlier than I did.
So I don't want to stereotype all INFJs as irresponsible doorslammers. At the same time, overzealous doorslamming does seem to be a predictable weakness in the INFJ's psychological makeup... like failure to set clear boundaries is in mine. Let me quote my own post from earlier in this thread: