fold the river?

[turnipmonster]

all my opponents were extremely loose preflop. however, the cap out of the blinds almost always means a big hand. I can't fold the flop or turn with the nut flush draw, but given I felt I was "drawing" I felt I should have folded the river, except it was a large pot so I paid it off with the always ugly overcall. thoughts?

Party Poker 5/10 Hold'em (6 max, 6 handed)

Preflop: Hero is Button with K[img]/images/graemlins/heart.gif[/img], K[img]/images/graemlins/diamond.gif[/img].
UTG folds, MP calls, CO folds, <font color="CC3333">Hero raises</font>, <font color="CC3333">SB 3-bets</font>, <font color="CC3333">BB caps</font>, MP calls, Hero calls, SB calls.

Flop: (16 SB) A[img]/images/graemlins/heart.gif[/img], 3[img]/images/graemlins/heart.gif[/img], 7[img]/images/graemlins/heart.gif[/img] <font color="blue">(4 players)</font>
SB checks, <font color="CC3333">BB bets</font>, MP calls, Hero calls, SB calls.

Turn: (10 BB) 8[img]/images/graemlins/spade.gif[/img] <font color="blue">(4 players)</font>
SB checks, <font color="CC3333">BB bets</font>, MP calls, Hero calls, SB calls.

River: (14 BB) 4[img]/images/graemlins/club.gif[/img] <font color="blue">(4 players)</font>
SB checks, <font color="CC3333">BB bets</font>, MP calls, Hero calls, SB calls.

Final Pot: 18 BB