To forgive means:
to let go,
to pass over,
to cease to feel resentment,
to cancel the debt that someone owes you (debt= their wrong towards you).
Jesus said that when we pray, we should ask God to "...forgive us our wrongdoing the same way that we forgive others when they hurt us or let us down." (paraphrase from the Lord's Prayer in Matthew 6).
What would it look like if God forgave me the same way that I forgive others (i.e. begrudgingly)? If you are anything like me (and most of Western society), you struggle to accept responsibility for your own wrongs, let alone forgive others when they have wronged you. It's such a struggle to 'let go' and to resist trying to prove to someone how 'wrong' they are and how 'right' you are!
How can I become more forgiving? "Forgive one another, even as God, through Christ, forgave you." Ephesians 4:32
The answer is to first experience God's forgiveness towards us. Why do we need His forgiveness? When have we wronged Him? Every time we make a bad choice, it hurts our Heavenly Father, just as it hurts us when those we love make destructive choices. And when we hurt someone else, we are primary sinning against God because He is their Creator and Saviour too.
God is much more interested in forgiving us than we are in asking Him for forgiveness.