[oneeyejak]

Betting every street means he either has you beat with AA KK or possibly but not likely JJ.... or he has the same hand as you.... or he just has a big beanbag and bet every street with a hand like AK.

Hard to tell, but you probably could have found out if you were beat by raising the turn.

Also, some stats on the guy might tell you if he was swinging at air.

I'd more than likely fold the river as played as your are probably beat. If he has AQ or AK, fine. Give him credit where credit is due because he is certainly playing like he has AA or KK.