What would you do?

last night I was using Facebook messenger, I found my message requests and found a ton of messages I never even knew of! Among those messages I found a message from one of my high school bullies. It was a letter of apology. I'm not quite sure how to react to this. After reading it I started reminiscing about my life back then, how it felt to be a complete outcast. To this day I still am, but I have the up most respect for who I am and who I become. Looking back on my life I would not change anything, only because everything that had happened to me has helped me become the strong humanitarian I am today. Now I left to wonder, should I respond? Or should I leave it be? what would you do?