DGU, as every, has a good, calm take on this.
Just for the record, my H is another for the loving childhood. He wasn't abused or hurt in any way in childhood, he grew up with two parents who loved him and showed it; he said that he always felt loved. There is the conflict avoidant thing, though, and if anything, the one thing that didn't happen in his childhood home was talking thing out. His parents never argued, he remembers one period of silence between them when he was young, so if they did argue they did it very carefully behind closed doors.
But despite great love from his parents the self-esteem must not have developed at some point; I remember him saying to me very soon after we met that he always felt a need to prove himself better than someone else.
Maybe it's because his parents were reticent; they were the worker bees, always helping, but never putting themselves forth for anything. They may have felt that they weren't "good enough", actually. I do remember them sometimes saying "oh, that's not for us"; i.e. that they didn't deserve something. I think for them it was more about being frugal; they had survived the war in extremely difficult circumstances and asked nothing more than to be able to live and raise their children, but that may have translated to H in a different way.
It may have been to do with material success, as they weren't well off, even if they were the same as their circle of friends. Or social class or something. I remember him saying that when he went to university he started associating with a "better class" of person, and it "pulled him up". So somewhere in there I guess he never felt good enough.
So is that the "initiatory experience"? Perhaps.
Someone here at some point said that he may not have been allowed to own his own feelings; that somehow makes sense.
This actually came up in conversation between my H and I a couple of weeks ago; we were touching on another couple going through this (yes....); where the woman threw the man out. He asked about them, I said that basically she was dissatisfied with life and had decided that her H was the cause. He said well, she has lots of psychological issues (which is true).... I said something in response, then said that by all rights it should be me doing this, as I was the one with the difficult childhood, not him.
Goodness -- a long answer to a short question.