I had a girlfriend in the past and I was extremely rude to her, it's been bugging me for the past 30 years.
What did you do to be mean to her?
There was this guy who had more money than me and I did mean things to her so she'd cheat on him with me
I understand that you probably didn't want to be in a relationship with your girlfriend, but being cruel to her so that she would cheat on you is not a good way to handle things. Just be honest next time.
I'm only human, I can't make all the right decisions.
I understand that, everyone makes poor decisions from time to time. But you need to take this as a learning experience and just be honest with your significant other next time.