Ephesians 4: 31-32
31 Get rid of all bitterness, rage and anger, brawling and slander, along with every form of malice.
32 Be kind and compassionate to one another, forgiving each other, just as in Christ God forgave you.
12 Not that I have already obtained all this, or have already arrived at my goal, but I press on to take hold of that for which Christ Jesus took hold of me.
13 Brothers and sisters, I do not consider myself yet to have taken hold of it. But one thing I do: Forgetting what is behind and straining toward what is ahead,
14 I press on toward the goal to win the prize for which God has called me heavenward in Christ Jesus
18 “Forget the former things; do not dwell on the past.
19 See, I am doing a new thing! Now it springs up; do you not perceive it? I am making a way in the wilderness and streams in the wasteland.
11 Fools give full vent to their rage, but the wise bring calm in the end
6 a time to search and a time to give up, a time to keep and a time to throw away
Bitterness is the price we charge ourselves for being unwilling to forgive. Instead make peace with it and let go. God loves you and that is all that matters.