I want to change my game.

That 2nd hand is a call for sure, there is only one combination that beats you: TJ (assuming he 4bets KK) and you already put like 44BB in the pot.

He might very well have the TJ, but against that you have 20% chance to hit full house (or quads), and at NL2 people overvalue top pair a lot so I wouldn't be surprised to see KT or KJ here.

3rd hand I would play exactly the same, 1st hand is also fine, your holding the second nuts so it's really unfortunate that he got the only hand that beats you, I would never fold 2nd boat.

Problem is pre-flop, your range is always dominated and behind the villain's, tighten up.

A8 AK, QQ KK, 55 QQ

Hand 1: I think opening A8s from MP is pretty wide but not wrong. I also think it's a cooler but keep your ranges sharp from each position to avoid situations like these.

Hand 2: UTG vs MP1 we can call with QQ. We should raise flop. How can he have you beat? With JT from UTG?

Hand 3: We should raise flop here. Call OTR is ok IMO.

I think from hand 1 and 2 you start to get biased and fold each time when you have a good hand. My suggestion is to record all good hands where you are ahead in equity and win vs hands when you are behind in equity and lose. You will see that eventually, you win more with the former.

Your overall approach is possible to execute profitably. Here are my thoughts on maniacal preflop 3-betting:

• Position, position, position, (am i repeating myself?), position, position, position, position,, position, position, position, position,...
• Cheap is the key. Make small 3-bets. Make small c-bets. It suffices.
• Each time you bluff (which is pretty much every time you press a button:]), target a hand (or a range of similar hands) you want him to fold. Assess the cost, and bet no bigger than absolutely necessary. (When preflop stealing IP, you actually don't mind a call, since, assuming you play well, you can steal a bigger pot postflop.)
• People will notice what you are up to (unless you play zoom).
• Steal much less on turn and particularly river.
• The third bullet implies you have to do a shitload of hand reading. Get good at that. Playing TPTK on the flop is easy, but figuring out whether a steal is possible, and, if so, how much it should cost to get maximal effect, is not. Board texture is all here. Definitely do not use a standard size for all boards.

When I play in super-aggro mode, a session graph typically has long rising segments (say 10 successful small/medium steals) followed by a big loss (unavoidable) with this pattern repeating. Obviously, the key to winning is to keep all those steals cheap, and to avoids the worst disasters when losing big ones. Naturally, you'll also flop nuts once in a while (or be second best with second nuts), but these hands play themselves, and have little to do with this.

And oh, did i mention position? Position, position, position, position, ...

EDIT: After reading your posted hands (and your stats of 22/18/14 = VPIP/OPENRAISE/3_BET ???) I have these general comments:

• Turning good calling hands into raising hands (stats indicate you do?) is not a good idea. You win more by calling than raising.
• Raising big preflop (like 3.5x) is not sustainable if you intend to raise with garbage as well. Something like 2.4x will get almost as many folds. (Besides, you don't mind calls per above.)
• Your bread and butter hands will be some that most people fold to an open-raise, say 8♦:6♦: or T♥:7♥: or K♣:T♠: . These are barely (probably barely not) worth a call. But they may be profitable to 3-bet. (Stats also indicate you are too tight open-raising?)

Thanks everyone and Especially YohanN7 for reading my post well and make all the effort to answer it with for me very useful info, Thanks again!

Yohan's posts are amazingly helpful.

Do you coach, Yohan? Or do you just generously contribute to the forums here?

Thanks. I don't coach, and, unfortunately for me, I am better at poker theory than actually playing. There are usually several hands in every session where I feel like biting my leg off one split second after having pressed the button:) In the forums, there's an undo button. In real poker, there's notX(

I hear you. The mental game is so challenging it's unreal. I've worked on mine tremendously over the past few years (on and off the tables) and I've seen, as well as felt, a lot of progress. Separating emotion from decision making is just absolutely critical when it comes to making financial decisions.