There’s this saying in Indonesian: “Nasi sudah jadi bubur,” which literally means the rice has turned into porridge.
We can make porridge from rice, but once rice turns into porridge, nothing in the world you do can turn it back to rice. This, as you might have guessed, is the characteristic of regrets. And indeed, it is what the saying is all about.
Bad things you do can not be undone — you just have to cope with the consequences and, hopefully, learn something from it so that you may not repeat it.
You might say that mitigation of the consequences is still possible and that’s one thing you can do to sort of undo the mistakes or make up for the guilty feelings you have.
True. Porridge is as edible as rice; it can even be more delicious than rice (if you know what spices and condiments to add) and more desirable in certain cases (like when you’re sick and the doctor recommends that you take only soft foods). But that’s besides the point. The point is: you can’t undo what’s been done.
In the same line of thinking, I once tweeted something along this line: A broken thing repaired is not the same thing as the one that has never needed repairing.
The act of repairing — no matter how successful it is — alters the thing repaired. A repaired thing may functionally be capable of performing the same thing as that that has never undergone any repair. But something in it is not quite the same if only for one thing, namely: the experience, the ‘tweaking’ … If for nothing else, this is what makes something done can’t be undone.