Saying a sin is wrong is not judging the person. Love the sinner, hate the sin. Looking down on your aunt is wrong because you, me and no one else are better or worse than each other. Along with mass murderers, fornicators, rapists, and liars and thieves. God does not put sin in hierarchy like we do. He sees all sin as sin.
And for Christians that believe in the Bible, there is and always has been one truth and one way... regardless of how many religions are out there.
You are right to say that judging others is wrong. The Bible says not to judge in numerous ways and numerous times throughout the Word. I align with what the Word says... and that is not easy to do. If something is wrong to God, then it's wrong, and I would be lying if I told someone it was right...
Jesus' Peace and Love, Meorah