Saying "I disagree" is not synonymous with saying, "your ideas, and therefore you, are stupid."
Let us not pretend to agree out of fear of damaging friendships. A true friend loves you for who you are, not what you believe. And in turn, we all must work on letting others know that they don't have to be like us to be liked by us. If we all agreed, if we were all the same, the world would be very grey. It isn't, so let's not pretend it is.