Sure. But the net value of choosing to walk away and doing it right is incalculable next to the amount of damage it can cause if you don't or pick a shitty method to walk away... Like cheating for example. It's not a crime to have the heart want what it wants, but if you're being a dick about it, that's not a high road either.

Though on the other side acceptance is important too, also realising "better" is relative. I know we all want to be the best in the eyes of those we feel that for, and if we aren't it's hard not to take personally, but understanding that better for them does not mean we personally suck is an important step and allows us to move on to finding someone who does appreciate us.