Start by acknowledging your emotions and feelings. Sentiments tend to grow stronger if they are left unexpressed or unacknowledged, so if you feel bad about something, put your ego aside, and admit it to yourself. Once you begin to understand how a certain action by someone made you feel bad, you can let the person know they hurt you. Say what needs to be said, get it out of your system, and finish it all off by resolving any remaining internal issues and feelings you might have yourself.
Mentally resolve that you are going to move on. Holding a grudge requires a lot of energy and leads to the build-up of negative emotions like anger, resentment, and frustration, all of which can weigh you down. Make the smart choice to leave it all behind, and clear up all the mental space that is being consumed and corroded by the grudge – after all, it’s all in the past now.
Choose to forgive. This does not mean that the magnitude of the way you were treated is lessened, or that the culprit is exempted from their actions. Forgiveness does not change the facts or mean that you have to forget and pretend that nothing happened. Realise that forgiving the person is an expression of your bigger heart, and an acknowledgement of the fact that everybody is human, and makes mistakes.
Accept the situation as it is. Do not hang around waiting for an apology or for a thunderbolt to strike the person who has wronged you. It is likely that the culprit has already forgotten all about the incident, and moved on, so there is no reason why you should let it plague your mind and destroy your emotional and physical health. Once you come to terms with this fact, you can begin to let the grudge go.
Distract yourself. If you look around, there are a million other things that deserve your time, focus, and attention. When you take it all into perspective, a grudge begins to seem like a small, petty thing in comparison. If you cannot distract yourself entirely, try changing your perspective on the issue – look at it as a learning experience which made you wiser, and search for other positives in the situation.
Finally, do not indulge the grudge. Once you have resolved to move on, stick to it, and avoid any thoughts or situations which might fuel the fire. Do not lapse into resentful thoughts and feelings when you are idle, and if someone around you wants to talk about the situation, let them know you have moved on and are not interested in talking about it anymore.