55, flopped set, two check-raise attempts, river fold

[btspider]

MP1 is a bit LAGgy over a small sample, but has shown a few winners.
CO has solid stats over a small sample (16/9/2.5).
Button is unknown.

Party Poker 2/4 Hold'em (8 handed) converter

Preflop: Hero is MP2 with 5[img]/images/graemlins/heart.gif[/img], 5[img]/images/graemlins/spade.gif[/img].
<font color="#666666">2 folds</font>, MP1 calls, Hero calls, <font color="#CC3333">CO raises</font>, Button calls, <font color="#666666">2 folds</font>, <font color="#CC3333">MP1 3-bets</font>, Hero calls, <font color="#CC3333">CO caps</font>, Button calls, MP1 calls, Hero calls.

Got dragged for bets, but this is fine right?

Flop: (17.50 SB) 4[img]/images/graemlins/club.gif[/img], J[img]/images/graemlins/diamond.gif[/img], 5[img]/images/graemlins/diamond.gif[/img] <font color="#0000FF">(4 players)</font>
MP1 checks, Hero checks, <font color="#CC3333">CO bets</font>, <font color="#CC3333">Button raises</font>, MP1 calls, <font color="#CC3333">Hero 3-bets</font>, <font color="#CC3333">CO caps</font>, Button calls, MP1 calls, Hero calls.

sweet flop. i intend to check-raise.. and follow through even though button raises. CO cap looks like JJ or an overpair.

Turn: (16.75 BB) T[img]/images/graemlins/club.gif[/img] <font color="#0000FF">(4 players)</font>
MP1 checks, Hero checks, <font color="#CC3333">CO bets</font>, Button calls, <font color="#CC3333">MP1 raises</font>, Hero calls, CO calls, Button calls.

i decide to check-raise CO's JJ+ again. when MP1 check-raises, i'm thinking JTs/JJ/TT.. all common limp-reraising hands for loose players. follow through with the check-3bet, despite the range i put him on? CO doesn't have JJ when he just calls the c/r.

River: (24.75 BB) A[img]/images/graemlins/heart.gif[/img] <font color="#0000FF">(4 players)</font>
<font color="#CC3333">MP1 bets</font>, Hero calls, <font color="#CC3333">CO raises</font>, <font color="#CC3333">Button 3-bets</font>, MP1 calls, Hero folds...

crap... if CO raises MP1's bet, i'm probably toast vs AA. button's 3-bet looks like an idiot AJ who can't read the action.. or an aggro (on flop) KQ? do i have the 4th best hand? surely not the best, so i fold.