We misunderstand grace because we have nothing with which to compare it.
Perhaps some of us knew of one whom modeled God's grace but that is rare.
More likely we have been told the words, "I love you and will stand by you 'til the end," but our humanity is flawed.
This causes us to crave unconditional love but we assume that such love cannot exist.
Receiving grace cannot happen by merely memorizing Scripture or reading the Bible but by the decision to put aside our compulsive habits.
We all have these habits. Rather than leaning into God's grace, we attempt to make our life happier via our own means and habits. We try to meet our emotional needs by our means rather than exposing our core being to God.
Only as we allow Him to take away our compulsive habits do we experience true grace.
We may need to reveal our deepest secrets to another so that we can walk this path. We will probably need to stop making excuses and hear another's advice. We will have to discipline ourselves to live differently which becomes easier over time.
God's grace operates differently to human love. We feel that we must work to deserve it. The beauty of God's grace is that this is not so. (Psalm 103:10)