River Makes me Trip Kings and Villian a Flush

[BigNads79]

Game: 10c/20c NLHE home game, 10 players.

Game is very loose, with some ridiculous overbets going on everywhere. Unfortunately, I had been extremely card-dead for the most part. I had recently won a big hand so I was feeling pretty good about being patient and picking my spots, until this happened.

I'm on the button, UTG limps and there is one other limper. I look down at AK (stack about $27). I raise to 60c, which had been my standard raise all night. Both blinds fold and UTG and other limper call. Flop is Kxx, two diamonds. UTG (Stack $20) leads out for $1, other player folds, and I 3-bet. UTG calls. He had been a pretty tight ABC player as far as I could observe, so I'm thinking he either has KQ, KJ, or maybe he has a set. The turn is a brick and UTG checks. I check behind, thinking I have him crushed and maybe he'll be the river if I show weakness. River is the king of diamonds and he goes all-in. I was sure sure sure he had a weaker king than me, so I instacall and then he turns over Q9d for the nut flush (I held the Ace of diamonds).

I guess I really should have bet the turn hard to take down the pot. I was a little afraid he might be slowplaying a monster and I just did not think he would call a 3-bet on a draw. I think one of the weaknesses in my game is not being aggressive enough when needed. Any comments?