All-or-nothing thinking leads to conflict. Acknowledging that partial progress is better than no progress is the only path to positive change.
Let's say you're a pushy vegan. Your mom isn't going to stop eating eggs because you call her a monster, but if you appeal to her kindness, she may spring for eggs from chickens that weren't tortured in an attempt to appease you.
Don't be too self-righteous to tell her that you're proud of her (even though you privately think pasture-raised eggs are still immoral).
Being an uncompromising person is the express lane to a miserable, lonely life.