@Stan - I'm not even saying you can't hate them. I'm not even saying they can't hate you.
What I am saying is that religions, and various groups in general, frequently come up with lists of stuff that they don't like so much. Take, for example, Islam. Have you tried to draw a picture of Mohammad for them? This is not an activity that they smile upon. One of their rules is "Don't draw pictures of Mohammad". And if you engage in that activity you are evil, deserving of death, and to back that up, they point to their scriptures. Your family would probably shun you if you did so, or even if you suggested it wasn't so bad.
We should be able to "hate" the practice. Denounce it, tell them its actually immoral. We can even tell them they believe lies, and are abhorrent to life itself. But they don't have to listen, and I can't force them to agree with me.
And they can't force me.
Undermining that principle would endanger that separation.