And here's the thing: not tolerating people being unkind doesn't mean that you can't have grace for people just being accidentally "rude".
If you point out that someone said something hurtful, & they didn't mean to be hurtful, they have the opportunity to clarify what they meant! They can say "oh, I'm sorry! I could see how that would be hurtful, but I really didn't mean it that way." But if you let it be, they don't actually get the chance to correct accidental unkindness.