[PokrLikeItsProse]

I've met many an internet player who says it is an auto-fold if you had gone all-in on the river. I've yet to meet an internet player who I think would actually fold.

You should have gone ahead and made a pot sized bet on the turn. Either he has an ace or he doesn't. The only reason to make a smaller bet is if you are trying to entice a small pair to call you down.

You should also note the blind sizes. If your river bet was more than half your stack, you certainly should have just gone all-in.