Hi Spook-

Bet the river. BB has been betting this all the way through and now suddenly throws on the brakes. This reeks of a busted two pair. If he's trying to be tricky and pull a checkraise on you on the river, fine, but I think you'll see a busted two pair most of the time here, and he's almost certain to pay you off.

I like how you played the rest of the hand, by the way. Forcing opponents to call two cold gives incorrect odds for gutshots and meager odds for bottom pair - this is your biggest worry anyway, as you aren't ever folding out a flush draw or OESD.