As the Baltimore Catechism
399. When is our contrition perfect?
Our contrition is perfect when we are sorry for our sins because sin offends God, whom we love above all things for His own sake.
400. When is our contrition imperfect?
Our contrition is imperfect when we are sorry for our sins because they are hateful in themselves or because we fear God's punishment.
Think of a child who does something wrong. If he's sorry because he's afraid his parents will punish him, he has imperfect contrition. If he's sorry because he disappointed his parents, he has perfect contrition.
When we repent are we sorry because we love God or because we fear something bad is going to happen to us?
As you point out, its rarely an either/or situation but usually its more one than the other.