I lost to set over set. Bad play or bad luck?

[jeeptj04]

recently i was playing a 1/2 nl home cash game and this hand occured.
utg raises to 15 hes been playing pretty loose aggressive, tight passive player in middle position calls 15. button who is tight aggressive calls as well and im in the big blind and look down at pocket fives i call as well.
the flop comes Kc5h6h
i flop bottom set. i check intending to check raise any bet and initial raiser bets out 20, tight passive player in middle position calls 20 and the tight aggressive player on the button contemplates for a while before raising it to 85 total.
i go into the tank and i try to think what this guy's range of hands is. i dont think he would call 15 pre flop with king six or just smooth call 15 with KK. i thought he could have a hand like 56 suited for bottom two pair or a hand like 47 or 78 suited where he would have a straight and flush draw. so after i think of what he could have i just thought to myself "when in doubt, push!" and thats exactly what i did. initial raiser and middle position caller fold instantly and its back to the button who takes a little time and calls with 6s6d. he had middle set. the turn and river blank for me and i lose a huge pot.
so my question is to you guys, how could i have played this hand differently to minimize my losses? should i have just folded on the flop when he raises to 85 or what? any insight from you guys would be great.

thanks