Your reaction to your aunt is understandable; no one likes someone who constantly criticizes others—especially when we know we’re also one of their targets. The Bible rightly says that “The north wind brings forth rain, and a backbiting tongue, angry looks” (Proverbs 25:23, ESV).
Why are some people so critical and negative? I’m not a psychologist, of course—but I’ve noticed that people like this are often very insecure, and are constantly seeking to build themselves up. One way they do this is by tearing other people down. But in reality they end up tearing themselves down also, because no one wants to be their friend. No wonder the Bible says that an undisciplined tongue “is a fire, a world of evil among the parts of the body” (James 3:6).
But being judgmental and constantly criticizing others is also wrong in the eyes of God. Setting ourselves above others is an act of pride—and pride is a sin. A judgmental attitude also blinds us to our own faults. (Have you ever noticed that judgmental people almost never criticize themselves?) The Bible says, “Do not let any unwholesome talk come out of your mouths, but only what is helpful for building others up according to their needs” (Ephesians 4:29).
Pray for your aunt, that she will realize what she’s doing and begin to change—with God’s help. Ask God also to give you an opportunity to confront her about her attitude—lovingly, but directly—and to point her to Christ and His unchanging love for her.