I don't want to force people to associate. I want to stop religions who force people not to associate.
What do you mean “forced”? Language matters here. They aren’t forced. They agree with the rules and therefore shun you. Or they could just talk to you anyway. They can do that. There is no gun to their head. But they agreed to the rules of the group, and to a large extent, agree with them still - enough to put them above a relationship with you.
Why stop with Polygamy? Why allow abortion?
What? I think you missed my point. BTW, I am against abortion based on private property rights, and think polygamy is perfectly fine, as long as it’s between consenting adults.