Maniac pumping the pot?

[colpres]

Situation is Me in big blind with J9 spades. Aggressive player UTG who bets with nothing raises, 5 callers, I call (pot:7 big bets)

Flop As, blank, 10s
Action is check, I bet, Maniac raises, all fold except Player 3, I call (pot 10 big bets)

Turn is spade - I bet with flush, Maniac calls, Player 3 raises
I think Player 3 has flush, but perhaps smaller - so I'll call and look for showdown for 1 more bet. Maniac also calls. (pot 16 big bets)

River is blank - I check, Maniac checks, Player 3 bets, I call
Maniac check-raises! Player 3 re-raises - (pot 21 big bets) Given pot size I call, but with horror watch Maniac cap! I call
All three hands are shown - Player 3 shows Ks2s for flush, I have J-high flush, Maniac proudly displays his Ace-6!
With huge pot I thought it correct to play on, but never anticipated the insanity of Maniac to drive pot to 4 bets with only a pair. Are there ways I could have played the hand differently to limit the loss on the hand other than folding a still potential winner with a huge pot? With the huge pot, would folding have been a terrible mistake?