Betting with the second nuts.

This hand happened to me about 6 months ago at foxwoods 4-8. It was about 4:30 am, and I was playing all night, the villian is the guy to the left of me is your normal weak passive player and I took some big pots off him earlier in the night with nut flushes and such. So one hand I look down at Q-8 suited in the blind and villian and I think 2 others are in there with me.

Flop comes Q-8-X rainbow, I checked the flop villian bet the flop other people fold I raise, Villian calls. Turn is a jack, I bet, villian raises, I 3 bet, villian calls. River is a Queen so the board now reads Q-8-X-J-Q, with Q-8 I have the second nuts, so I check it trying to induce a bet and sure enough he bets, I raise him, he 3 bets, I make it 4 bets, He makes it 5 bets. This has me really afraid now, he could be doing this with JJ with jacks full but he only limped preflop, so I flat called his raise and he turns over Q-J off for the nuts.

Now my question is when I have the second nuts in limit heads up how many bets should I be willing to make. I like to limit myself at 6 bets. Should it be more or would it be situation dependant depending if I'm up against a rock or a super loose player. Like I said he was really weak passive, and He could have been doing this with pocket jacks.