The best way I know of doing this is to remember that when you raise your vibration, you are changing frequencies. Which means that all things exist simultaneously. And if that is the case, you are actually changing into a different "you" when you raise your vibration. As soon as your vibration shifts, you actually aren't that same person you were before- and the past can simply fall away if you relax into the concept. There's a great Bashar video that explains this, I'll find it.
Basically, you jump to a higher frequency, and the past ceases to exist! I've experienced this firsthand quite a few times lately. With my guy, I focused purely on the "new" me that had no past, and he behaved as though the past didn't exist! Arguments seemed to be wiped. Same with my father. He was extremely rude to me one day, and instead of arguing with him, I put ALL my focus on the positive side of him, and how much love I actually have for him. I let go of my anger and my need to yell and scream and instead focused on love. On the desire to love instead of "being right." And for the first time in about 20 years he apologised profusely and said he was ashamed at his behaviour!
Forgiveness wipes the past, beautiful people. The mess will simply fall away and freedom becomes yours. 💜