Good questions. Returning to sanity, civility, and moderation means that everyone has to be willing (at least on some issues) to lose or to not get what they want. That's the crux of it.
If people aren't willing to lose or if they demand all that they want - without any compromise, equivocation, patience, or humility -- then everything breaks down. And all hell breaks loose.
In addition, people have to stop seeing their goals, agendas, and ideologies as the end-all-be-all. They have to stop wrapping their identity and self-worth in public policy or public validation. And...
People need to stop dehumanizing those with whom they disagree.
Human beings living together requires give and take. If it's all take and no give... civilization ends.