You feel sorry for everything, but what for exactly? Because I remember all of it. Do you?

Just saying "sorry" isn't enough good of an apology. It's generic and it doesn't mean a thing.

It is good start of a sentence where you are stating what are you sorry for so the other person knows that you acknowledged what was wrong and that you are aware of what actually hurt them.

This came to me as a really hard but much needed life lesson!

The tree remembers, the axe forgets.

I don’t personally feel sorry but saying “sorry” is more of a diplomatic act. Diplomacy is important.