This conversation first came to me in the context of Freemasonry, but I think it will translate well to lay terms.
The question posed to me was, at its essence: If people are doing something they believe is right but is diametrically opposed to my principles, how do I make them see the light?
My response was this: It's not your job to bring others to your view. It's your job to bring yourself to love people, even if you believe they are wrong in their thinking.
I think we'd all do well to attempt to uphold that ideal. It's not easy, and it never will be, but I think it's important.