Common flaw at the lower levels

Attachment to the money you have invested in the pot is a serious problem for a lot of players. They can't let go from the idea that those chips are still theirs. They raise it up from position after some limpers with the a-k(no spades). Flop comes down a-7-8 with two spades. The limpers that call the raise check to him. He bets out at almost pot size. UTG +2 had a pp of eights and the MP had 9-10 spades. Big pot and the A-K doesn't get away. Why? He thought he was good with tptk? Not really, he knew he was in trouble with all the action. But he had money in the pot and he just couldn't face that he might just have to dump that money and look to the next hand.
Now, two things you should try to be aware of at the table. First, when you are putting too much value into a hand. One pair, no matter how big is still just one pair. There is a lot of ways to lose with that. Just go through the list on what might be beating you and what would fit in your opponents betting of the hand. Yes, I am simplifying things. You could have trips on a strait board or flush board. Be willing to lay down a big pot when there are a good number of hands that can toss yours into the dumpster with the other trash. That might occasionally mean you are tossing a winner but sometimes you have to do that.

Second thing on the to do list for this is identify players with this habit. Overplaying any pair, not laying down on a flushing board, the guy who calls you down with a pair when the turn hits a higher card. You need to know who will pay you off. These are the ones that I will call more with second pairs and draws. Because if it hits, the impied odds are more then good. They don't have the ability to mentally divorce themselves from the money they have added to the pot.

Let's try to describe this in a different way. You all had relationships that didn't work out. They drove you crazy, it was torture, but you walked out the door. Next relationship you see some of the same traits, you leave but it wasn't as crushing. Next time you even see the traits, the door shuts and you are gone. No pain.

Now, you are putting chips in the pot. You have done this plenty of times. The hand goes bad. Simple, right? Walk out the door.

Just one of the many small steps in building yourself into a better player.