This one's easy. Everything about this hand should put up a yellow light (or red for that matter) to you. Everyone limped, so since we don't know what the people who folded had, we can say no one made a really big mistake pre-flop. Personally, I fold the Q 10, and probably raise the suited connectors with so many limpers. After the flop, you had the best hand, but you were not the favorite (if you were, it was barely in your favor). SB was right to bet with an open ended straight flush draw, you were right to raise, Q 10 could justify a call by putting you both on a straight or flush draw, but he really should have folded to a bet and raise, the rest...who knows. But with 5 people in this pot, you have to figure someone is on a open-ended or flush draw. HAVE TO. I think this is your mistake. When the 6 comes, and a caller becomes a raiser....odds are he just hit. At these limits, there aren't a lot of people who know how to represent hands. They telegraph their hands to you, as did SB in this instance. Since the pot was getting large for these limits, I can justify you calling or even raising, but you had to do so with the knowledge that you were probably behind. You're hoping for a miracle 9 or 2 and a 5'th street cap. You even had pot odds to call the final bet, even though by now you should suspect you've lost. So, the only mistakes that I can see that you made are raising the 3-bet (even though it can be justified, it's still not a good idea) and labeling SB an idiot. Of course he knew what he was drawing for. Why else is he betting on his draw, calling your raise (but not re-raising) and then 3-betting when he hits. To me, he played the hand just right. He was able to limp in with a drawing hand, get a good flop, and hit his draw. He really didn't do anything wrong at all. The Q 10, yeah, an idiot. SB, I'd say he simply outplayed you on that hand. We all get outplayed more often than we'd like to admit it. It's just part of the game. Get used to it and let it go instead of venting on here to try to get somebody to make you feel better about your mistake. I'm not trying to be rude, that's simply a lesson everyone has to learn at some point if they want to play cards for money.