I'm going to be giving a pragmatic answer, so here we go.
I, as a human being, am a social creature, and so while it may not mean much to my conscious, I've noticed it affecting me quite a bit.
I find it hard to believe that noone is affected by other people's opinions to some degree, as if everyone had a poor opinion on you, it's more likely that you're deluded in thinking you're 'right'—I don't know how you scale right and wrong though, so I can't speak for that—than anything else.
Though it does depend on just whose opinion it is. A stranger walking down the street's opinion won't carry much if any weight, but a personal friend's most certainly will to me.