I'm not interested in discussing any religion in theory or in practice, unless that practice makes it way into legislation. Your right to swing your arm ends at the point where your fist contacts my nose. I don't mind your offer to sell me music, although you are right that I'm not buying. It's when you try to force me to listen to it that we have an issue.
Is it really that hard to understand? The founding fathers understood it quite well:
Your mistake is in believing that because you don't hold certain morale values, your neighbors are prohibited from expressing and lobbying for their morale values. The only "separation" possible between "Church and State" is the establishment of an "authorized church" (or "State Religion"). Community morale standards, which almost universally evolve from religious beliefs, were always intended to be the glue that held the Republic together.
If you look at the principles embodied in most major religions (not the practices carried out by their followers) you will find many similarities in the concepts of "right" and "wrong" as they relate to how we are to treat one another. English Common Law - the basis of our legal system - is rooted in those beliefs and in the common practices which made them acceptable to most of the population. The forcible separation of "religion" from public discourse since the 1960s has allowed us to get to the point where we don't any longer understand how our governmental system works; we no longer have a shared set of moral values as a standard by which to judge behavior; and we've lost the moral compass and shared values which made us a "Melting Pot" instead of a nation of Balkanized special interests.