At least I know everyone will read my post now.
Here are some questions I have.
1. What role, if any, should sex play in the government? Specifically, why should we get tax perks and certain privlidges just because of sexual unions?
I hate to break it to you, but just because YOU think of these relationships primarily - or perhaps only - in terms of sex, they are NOT primarily sexual, and the government doesn't deal with them on that basis. Notice, if you will, that when a married couple files a joint tax return, for example, there is no box to be checked for whether they have sex with each other or not.
2. Should sexual relations imply obligations legally of any kind? Should a spouse be allowed, for example, to simply leave all of their estate to someone other than their sexual partner, or should the fact that two people had sex together for a specified time make them legally obligated to get a cut?
Once again, these relationships are NOT primarily sexual in nature, as a rule, nor is that the basis on which the government deals with them.
People are allowed to leave their personally-owned property to anyone they wish, and I am not entitled to any of my husband's estate on the basis of having had sex with him, but on the basis of having married him. Whether or not we EVER had sexual relations, so long as neither of us complained officially about it, is irrelevant to that law.
3. Why buy a marriage license? Why should we pay?
The purpose of the marriage license is to bring the relationship into the legal purview of the government, for the purpose of making it an official, binding legal contract, as a marriage happens to be. The fee charged for it, which is generally nominal, is to defray the administrative costs of doing the paperwork.
4. Should those who are monogomous be allowed to discriminate against those who are not by having special government privlidges over them?
Sorry, but that's not what's happening. Once again, you are projecting your personal view of relationships onto the whole world, and assuming that everyone else views them, and has always viewed them, the way you do.
Society recognizes and encourages some relationships - NOT sexual - over others because those types of contracts have, typically in the past, redounded to the benefit of society as a whole.
5. What about asexual people? Shouldn't they have the same rights as those who are sexually active? For example, if two people live together and are the best of friends but don't have sex together, why is it they can't file jointly with taxes and provide the same privlidges those that have sex have?
What ABOUT asexual people? They HAVE the same rights as everyone else. If they perform the same actions as other people, society will give them the same treatment. Once again, no one anywhere is being forced to check any boxes regarding whether or not they have sex with their partner, or with anyone else. Society and the government DO NOT CARE about the sexual activity in your relationship, in this respect. YOU see it that way; that doesn't make it the way it is.
Asexual people who remain single, just like single people who **** everything that buys them drinks the bar, do not benefit society in so doing, and so society makes no effort to reward or encourage that behavior.