quote from How I Met Your Mother aka best comedy ever:

Lily: OK, yes it's a mistake. I know it's a mistake, but there are certain things in life where you know it's a mistake but you don't really know it's a mistake because the only way to really know it's a mistake is to make the mistake and look back and say 'yep, that was a mistake.' So really, the bigger mistake would be to not make the mistake, because then you'd go your whole life not knowing if something is a mistake or not. And dammit, I've made no mistakes! I've done all of this; my life, my relationship, my career, mistake-free. Does any of this make sense to you?

Ted: I dunno, you said mistake a lot.

i've made loads of mistakes. and most the time, i make the mistake knowing it was a mistake. and now...i sorta wish that was a mistake. but it didnt matter at all. it wasnt even fit to be a mistake. so who cares?
everything has just been made equivalent to nothing. how should i feel? i dont know, i really dont. cos i dont feel anything and im so numb already it dosent make a difference.