In short, I get over people easily when I am self aware of my emotions and thoughts, and understand the feelings of people around me.
To cite an example, I have had times when people treated me unfairly. I was juggling between two jobs, and was also drafting up university application. It was an immensely stressful period for me, since I also had to deal with the fact that I did badly for my second round of exams. It was a constant toughness, I worked from 5am to 11pm, and napped in between my breaks. One evening, a colleague entered the room and saw my belongings splattered across the table. I was working on my application essay, my laptop bag and research materials spread all over the work table. He took it upon me, and gave me a lecture with a condescending tone, asking me if I had any respect for the workplace and myself. I think he crossed the line when he commented that my own bedroom is probably as messy as this, and it hit a nerve really badly.
I never talked back to him, nor confronted him about that. Because, while my colleagues were busy defending me and arguing with him, I noticed his frustration with the workplace and the anger directed at me that night was not meant for me, but the first shift at work. I just nodded my head throughout while they bickered, slowing down to a consensus. The event was over, it was over. It took me a while to recover since he struck a nerve related to my emotional trauma, but I got over him. I was aware of my built up exhaustion coupled with my emotions all the while - me being scared, me feeling unjust, angry, hurt, disappointment in myself for not speaking up, but more importantly, I knew if I spoke up then, it would have worsened the situation. I am also aware that he was frustrated, so I focused all my energy on understanding where it was stemming from. I saw two sides of the coin, and I recognised that what happened was not personal, and is not meant to be.
I separated myself from the situation to evaluate my emotions, versus others. There is simply nothing to hold grudges for, as it does not solve anything.