Having said all this, I am quite happy to read stories which show insecurity and/or manipulation if it is well done and can convince me of the reason for it.

Oh yeah! Me too. That's the essence of a good writer, when it comes to "far out" characterization, isn't it? That the power of the writing compels you to believe at least while you're reading the story -- at least enough that you accept it as a possible view of who the guys would be, even if it's very different from your own view.