3/5 aces up on river facing scary board

[kevdawg21]

Live game, 3/5 blinds. Villian in this hand is loose and very aggressive. He and I are both regulars and have played several sessions together. I'm probably seen as tag.

The table has been pretty tight, except for the BB and villian. BB tried to bluff me off of a hand recently with a big bet on the river, which I called with 2nd pair. Also recently, villian bluffed the flop and turn very strongly against a weak player and was called down, but made a runner straight on the river. Villian's bet on the river was $200 into a pot of about $250

Relevant chips counts:

Hero $400
Villian $900
BB $200

Villian is button. Hero is utg+1 with A [img]/images/graemlins/club.gif[/img] T [img]/images/graemlins/club.gif[/img]

Preflop: 1 fold, hero raises to $15, 5 folds, villian calls, BB calls.

Flop ($43): A [img]/images/graemlins/spade.gif[/img] Q [img]/images/graemlins/diamond.gif[/img] T [img]/images/graemlins/diamond.gif[/img]

BB checks, hero bets $15, villian calls, BB calls.

Turn ($98): 8 [img]/images/graemlins/diamond.gif[/img]

BB checks, hero checks, villian bets $40, BB folds, hero calls.

River: ($178) K [img]/images/graemlins/club.gif[/img]

Hero checks, villian bets $80, hero...?

What do you all think? I probably played the hand badly. I bet the flop weakly hoping that villian might raise me with air. After he called the $15, I put him on either a weak ace, a bare K or T hoping to catch trips/2pair, or something like JT, a straight draw and a pair. I didn't think he had diamonds since I think he would have raised me on the flop with a flush draw. I thought BB must have been on a draw for sure. He might have the diamonds. I should have bet the turn, but I wanted to keep the pot small. His bet on the turn surprised me; not that he filled the void with a bet, but that his bet was so small. His previous bluff bets had been stronger. This bet looked like it wanted a call.

The river was a nightmare as far as I was concerned. If he thinks his hand is best, it pretty much has to be. His bet gave me pretty decent odds on a call, better than 3:1.

Insights would be appreciated.