To remember the lows better is human nature. But as long as you don’t fixate on what happened in the past, you will be fine! You had an argument, again that’s absolutely normal, and to throw everything away would be silly. My BF has this great ability to turn argument into silly/funny thing. We end up laughing. So take it easy, arguments are good, don’t bottle things up and laugh. To change yourself at adult life is not easy, it takes time and dedication. I personally love yoga/ learn to be present/ there is million good books how to be a better person but they are no use if you don’t follow what they preach! That’s why it’s hard to unlearn your habits/behaviour. It’s not about making mistakes in life, it’s about making a mistake and trying not to repeat it! To get out of the pattern is being wise.