basicaly i have in CO and utg limps so i raise it to 4.5bb, Co calls, and SB calls(as usual, almost family pot :/)
flop is , 15.5bb pot
i bet 13bb pot in intent to fold to a reraise
anyhow..Co calls and sb folds..CO is 24/11/2.5 so seems quite decent
turn is , pot is 41.5bb and i bet 25bb, villian calls..
is this the most obvious turn check of them all? what do i do if i check and villian bets(since he thinks it was a cb with any two almost)
river is , pot is 91.5bb.. i valuebet 20bb and he pushed for total of 50bb
i call
thoughts?( i know i misplayed it..real question is what would be the optimal way to play it?)

I think you meant to post you were in the MP, right(You have yourself in CO and opponent in CO)?

As played, call on the river is a no brainer. If CO isn't someone who is going to call that flop without a big piece then I'm checking the turn. If your read on CO doesn't include any bluffing or overvalued hands or the ability to make moves here, then yes, seems like a check on the turn with a probably fold.

I don't know an optimal way to play it...harder to provide that unless your read is pretty solid and you have good information on how he plays postflop. This could be a hand where you could CRAI on the turn, hopefully pushing opponent out, but I think the real problem lies in being OOP with a big pair on a board that probably screams set. Keeping the pot small and possibly giving up on it seems to be your best options postflop.