I hate Pocket Kings

[CheckCheckCheck]

Hello, I'm fairly new to the game (been playing about 6 months) and my experience is mostly home games, online and two live tournaments (placed 6th/45 and 11th/45).

So I have a question for you guys and gals. Obviously, KK is a monster hand but it seems like every time I get them, I lose with them, and it always seems to be the same way. An Ace comes on the flop and I lose to the dummy who played A6 offsuit from 2nd position.

Here's an example of what I mean; this happened in my last tournament and it seems to happen a lot: I'm in maybe Middle/Early Position with KK with a raise in front of me (the dumb A6 guy) of about 2xBB, so I re-raise to a little more than the size of the pot. He calls.

The flop comes 2c 8s 5d. Looks like a pretty safe flop for me and all I have to worry about is a set. So, he makes a bet of about half the pot and I raise about twice that and he calls. The next card is the Ac. He makes a bet of about the size of the pot and I call. River is 2s. He checks and I check. And of course I lose the pot.

Did I do something wrong? Should I have gone all-in or way over the top on the flop or something?

It just seems to me that EVERY time I have KK, an Ace comes on the flop or turn and I lose to someone holding A6 A7 or something. How do you guys play KK?