Regret is closely related to our own belief that we have failed to make the right choice and that things would've been much better if we had picked a different option. But is it possible to truly know which one of the many choices we have every time we need to make a decision is the right choice given our limited ability to only live one branch of reality from that choices? If there is no way to prove the right choice, does the right choice then even exist? If it doesn't exist, does regret exist? I went into deep thinking mode for days on this, try listening and see if it makes sense or turns out to be utter nonsense.