I'd say it's a bad fold but your post is a little too incoherent to see who raised when. Who bet the flop, the SB, BB or UTG? The CO bet the turn? Looks to me like CO is saying he has an ace or two pair or something, but being 3-bet on this turn doesn't necessarily mean you're beat. He could be doing this with a big ace or an inferior two pair.

The only way I can see folding this river is if the flush comes and the other players go nuts.

By the way, please include pot sizes in your posts. By my math, you're getting 18.5:1 on this call. A fold is very, very bad.