I don't want to focus on the moralism of "wrong" or knock the hermit or in-society-but-anti-social life, so I'll take this as "productive" of a direction as I can: *if* you see it as a self-harming behavior, then perhaps you want to learn and practice ways of dialogue that express and define your views rather than argue? Looking at it more like an explanation than a fight helps, even if you feel the other people just repeat bullshit they've heard.
Although I have a fondness in my heart for the rhetorical equivalent of the sledgehammer-to-the-face approach, if you want to talk to friends or loved ones you might aim for mutual understanding of your differences rather than anarcho-missionary as a first step. Having each of you able to say, "here's what X might think about Y" can at least make it more comfortable sometimes, when you can agree to disagree. Many people need to more gradually decrease their cognitive dissonance for it to work so going all-out just goes over their head and sounds insane. Not everyone though, and we appreciate many an anarchist curmudgeon among us.