Although we impact each other throughout our lives, real, meaningful change very rarely happens (after 20 years of "self-work," I speak from experience, alas!). Most of us die with the same patterns we developed in our first 7 years still firmly in place.
I'd say change never comes about through the willed intervention of another save in a negative fashion, by causing trauma. Of course there are overt ways that people change us - by saving our lives or giving us STD, or whatever; but even then these people are only agents of change who happen to cross our paths and so impact our lives. If it wasn't them, it would have been someone else.
Our idea of having some sort of say about the way our lives unfold is largely illusory. Think of it this way: the Universe is a larger organism that is operating intelligently according to its own "agenda," and we are microbes within that organism and so, inevitably, part of that unfolding agenda. Do we consider the cells in our bodies to have free will? Maybe when they develop cancer! Otherwise we consider them merely a part of the greater working, with no autonomy outside of mutiny, ie, "disease."
What I mean, maybe, is that - accepting that we can't help but influence those we interact with - we should never try to change another person, because to do so would be to impose our belief/value system upon them. We are invariably been driven by our own "patterns". Our motives are never clean.How many of us even know what's best for ourselves? If we did, would we be so tangled up in addiction, frustration, sexual obsession (aka "romantic love"), self-hatred, and all the rest? So then, where on Earth do we get the idea we know what's good for others?
It's a socially endorsed form of egomania, and it's very evident in the APC (alt. perc. comm) in the way people platform with their ideas under the assumption that it's "important" people know about them, when really, they are simply trying to get attention to validate their own beliefs. Myself included with this post!