[El Diablo]

dlp,

"If anyone finds a fold on the river, please say why"

It's only worth responding to a post like this if we assume what you write is valid.

"in my experience ... a river overbet like this is almost NEVER a bluff"

"he knows I love to call him down"

"he can't really be bluffing."

"it certainly looks like I could have been flushing given the action."

"my physical read of him ... was that he was absolutely not bluffing."

"he pretty much had to have a flush there."

In which case, this is an easy fold.