Others' moral views are judged wrong to the extent that they clash with my own deeply felt moral sentiments (which are a part of MY reality). To whatever degree possible I try to ensure that my moral perspective is internally consistent, but you're right, ultimately I am just deciding that I am right and that those who disagree with me are wrong.
In my honest opinion that's what everyone does, whether or not they are willing to admit it.
On a related note, people keep insisting that it is possible to correctly comprehend bits and pieces of reality (defined universally), if not reality in its entirety. I disagree. Without reference to reality in it's entirety, one loses the proper context with which to interpret bits and pieces of information as they bubble into our consciousness. Attempting to discover the ultimate meaning of a small slice of reality is akin to watching only 3 seconds of a movie and trying to accurately interpret what was going on in that instant. It cannot be done. Accurate comprehension of reality and correct moral principal is the domain of God and none other. This is why people turn to religion -- they come to recognize their own limitations.