What's your breakup style?

The only breakup I had was just a relationship trailing away...so basically we didn't break up, we stopped meeting and communicating because we both were busy and it just stayed that way. It suited me and I have no idea how he felt about it at that time to this day but about 3 years later he suddenly wrote to me "if you're still mad at me, why don't you untag me on your Facebook photos?" or something about those lines. I was pretty much taken aback because I thought it suited him just as much as it suited me and thought we were good. I still have no idea what should I have been mad at him for. 😆