Not playing my optimal game

I have been playing poker for about 3 years - sometimes online, sometimes at bars (essentially free games where you compete for a bar tab), and more recently at casinos. I consider myself a decent player who still has a lot to learn. However, I'm really having an issue with playing cards that I know I shouldn't, and I think it is hurting my game a lot.

I know which cards are good, which are marginal, which are drawing hands, and which are trouble hands, but sometimes I make decisions that I know that I shouldn't, and really beat myself up about it afterwards. For instance, last night I was playing a live game, and having a run of bad cards. I was dealt A9o UTG. I knew that I shouldn't play it, but I went against my instincts and limped in. No one raised before the flop, but there were 5 people in. The flop came A K rag (don't remember suits). I bet, everyone else folded except for the person on the button who raised. I really felt she had me beat, but I thought that if I was going to play A9o in the first place, and the Ace came out, what business did I have folding, especially when I had so much committed?

Long story short, she had big slick and won with two pairs - which is bound to happen when I play A9o UTG with 10 people at the table. When I am mature enough to fold Ace rag in early position, it seems that I always get something like two pair on the flop, which makes me want to play it next time. I know that this is an overly emotional way to play, but I can't seem to stop myself sometimes. I also see a lot of other players playing loosely - and winning way too many pots that they shouldn't, and it affects my game. I feel that I should loosen up if everyone is playing loosely.

Does anyone have any thoughts on how I can prevent myself from making these disastrous decisions? I mean, it's crazy - if I was watching that hand rather than playing in it, I would have told the person with A9o to fold immediately when they got reraised (by a good, tight player). Instead, I threw good money after bad, because I let my emotions get the best of me.

you will find the answer within the thread young grasshopper...
I know what you mean, just last night I looked under my kitchen sink and saw some household cleaner and thought would it be wrong to drink it knowing it will make me sick but drank it anyway(sarcasm)......Do you see what I'm saying?

It doesn't sound like there's much anyone could tell you to give you more discipline; it's just a matter of getting that discipline yourself and telling yourself it's just not worth it. I guess you could try to take a 10-second time before playing any hand and just step back and think "Listen to your brain; is this a good decision or a bad one?" then act accordingly.

I myself have a problem with in-the-moment calls sometimes; I've ended up writing "STOP AND THINK" right under my monitor to make sure I make a conscious decision every time instead of getting my money in bad. Don't quite know what to tell you with respect to live poker, though, except 'Don't do it'.

Think about every decision before you make it. Say to yourself "I am <proposed action> because <reasoning behind proposed action>".

So, "I am limping A9o UTG because...". If you can't think of a suitable way to finish the sentence, the action proposed is porbably not the best one.

"I am folding A9o UTG because..." is a far easier sentence to complete, of course. Generally speaking, the easier the sentence is to complete, the better the action.

If seems to be that you know that this is answer to your question already though, and just need to apply it.

Ive realized that this happens to me sometimes when I play for too long at one time. If I have been playing for over an hour say, sometimes I get bored and start calling hands I know are bad. I have to stop, do something else for awhile and come back and play later if I feel like it. Maybe if you are playing for extended periods of time and this is happening to you, you should take short breaks.