The gospel frees us from being self-righteousness, judgmental, and pretending to be someone we aren't. Since our acceptance with God is not rooted in what we have done for him, but in what he has done for us, we don’t have to pretend to be someone we are not. There is great freedom in that.
As you grow in your understanding of the good news about Jesus, you will increasingly see two things simultaneously - God is holy and you are sinful (building a life apart from God with yourself at the center). Without the cross covering the gap between those two realities you will be motivated by pride on the one hand (religion), or despair and depression on the other.