When to lay down KK preflop?

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I got a bad beat again in PP NL game. I hold KK in BB, button raise, I reraise, button raise it back, I push with KK. The buttons holds AA.
how would you handle this case when you hold KK? Just call the reraise? If the flop is blank, and button push, would you call ? It is my at 4th time holding KK and lose to AA. Eech time I pushed before flop.
some pro do lay down KK, but it is really hard to me to do that preflop.
thanks a lot!