I don't know why INFJs have a tendency to do this more than other types. It seems like irrational/harmful/unproductive behavior. Why not address the issues earlier than wait till they get to some kind of boiling point and then cut the person off.
A couple of possible reasons for this:
Firstly, if a person has a value to keep the peace with others and is idealistic, they may feel they can tolerate a lot of crap from others. They put pressure on themselves to take it. A value of keeping the peace or a value of not controlling others can result in the assumption you have to take a person exactly as they are. Shakespeare even wrote a sonnet about it "Love changes not with its few short years..." Then the idealism breaks down and the person hits a wall and cannot cope with the toxicity any longer and has an emotional breakdown. I value not controlling other people and throughout my life have come to a conclusion that change is a rare occurrence in any human. Slight modifications can sometimes be made, but I don't think people change much. If you cannot accept and relate to someone exactly as they are, don't hope for change. Working on a relationship requires two people. If only one works on it, then there is little hope for improvement.
Secondly the person may be trying to address the problem in the harmful relationship and the other person cannot hear it, so eventually there reaches a point when they stop trying to communicate and just leave. There are a lot of people in this world who cannot hear certain things. I would not be able to map it to type because I've seen it in so many contexts. I have a number of teenage students (sometimes even elementary) who cannot hear me. Sometimes it is rebellion, but sometimes I can tell they actually cannot hear me in a lesson. For the teenagers I think they have been told what to do so many times that their quota is met and they actually cannot hear anything else. I tend to give those students free-range to get lost in their own little world. I have also experienced this in personal relationships where I tried over and over to communicate and the person couldn't/wouldn't hear me. They would look up from their gameboy and pat me on the shoulder a couple of times and continue playing. It wasn't malicious, but a blockout of the outside world. The person who did that was an IN-- type who had grown up in a chaotic environment where they had to learn to tune out all social noise. When an idea does not compute with a person's internal framework of reality, most cannot hear it. This is possibly true of all types, but only differs in the degree to which it happens and the type of information they cannot take in. In my experience in the world it is a fairly extreme, common problem. I don't have an answer of how to break through that, so I tend to find ways to cope around it or discontinue trying to connect.
I experience it with technical data. If someone starts explaining to me all the steps to diagnose and fix a technical system, I look at them and strain to hear, but the words start sounding like Charlie Brown adults after the first couple of steps. The same is true when people describe all the steps for a recipe, or law, or accounting. I can hear the first part, but then my mind glazes and I'm conscious it's happening, but I can't stop it unless I write it down and go over and over it later. For me Si and Te are my glazed data. For others Fe or Fi is their glazed over data, etc.