Apparently by telling them that they're going to hell and cutting them off.
Your characterization is not reflected by any doctrinal statement from any conservative denomination that I am aware of.
Wow, that’s quite a distorted view, but I think you’re just covering for something else.
Most anti-theists have some deep seated reason for being that way but cover it up with some strange, often “reason based”, excuse for rejecting theological truths that would be available to an open mind.
If you’re honest, do a “thought experiment” like Einstein, and ask yourself what you’d have to give up in your life if you chose to follow Christ. Then you’ll understand your own resistance more.
The one extreme or the other nonsense is a leftist argument. As Christians, we are not supposed to approve of behavior that the Bible forbids. That does not mean you hate or fear the person.
You seem determined not to get the biblical message of saving grace for the repentant individual.