I believe that some psychological "disorders" stem from a personality attempting to do actions/behaviours that run counter to the original type.
For example: An NeFi labeled with intermittent explosive disorder as well as borderline personality disorder.
In this particular case, the label was based on a combination of two things. ENFP actions combined with "learned" Fe attempts. (I use the word "learned" because attempting Fe was a long term survival mechanism.)
In another topic I mentioned what happens when an Fi attempts to Fe on a regular basis.
1. Basically, an Fi Fe's for an extended period of time. This creates internal conflict.
2. Eventually the Fi is going to put it's foot down and attempt to bring order back to the personality. (Hence intermittent.)
3. Usually by then, things have progressed so badly that the Fi comes out rather abruptly. (Hence explosive.)
4. People expect further Fe behaviors and consider the sudden Fi to be a sudden switch in personalities. (Hence borderline personality.)