Ob-La-Di, Ob-La-Da
A lazy way of saying 'whatever' but with more attitude and less brainpower. It's like when your mom says 'oh well' but with more sass and less regret.
My brother said 'ob-la-di, ob-la-da' when he failed math.
My friend said it when his phone died in the middle of a text.
I said it when my mom yelled at me for eating cereal for dinner.