It is said that blackjack is a card game played by people, while poker is a people game played with cards. And I really can't say it more accurately than that. There are a lot of card games out there that simply rely on the cards that are dealt.
Solitare, for example. There isn't anything you can really do to influence the game one way or the other. Oh sure, if you have a choice of moving two different Kings to an empty slot, one could end the game while the other could start a fast track to victory....but it isn't like you actually controlled anything with the decision. All you did was move a King.
In poker, you can control the outcome of the situation by not doing anything...and that is very powerful.
For example, you hold 2-3 in your hand, and the flop comes A-A-10, and you check. The other guy could be holding K-K, but your check would cause some concern with him. And I would bet that your check would cause him to check, because the fear of betting, and getting check-raised would be pretty strong. Whereas if you bet, and he reraises, you would be forced to fold. So by simply doing nothing...checking...you have a direct impact on the way the hand proceeds.
I once got a man to FOLD by calling. Try that sometime. I had raised preflop, and he called from the big blind. The flop came down, and he immediately bet out...and I immediately called. The look on his face was priceless. I knew immediately that he had caught top pair (a King), and I was holding simply pocket 10's, but I also knew there were alarm bells in his head that could wake the dead on Christmas. It was obvious.
He said "I'm about to get hurt, aren't I?" So I replied "Only if you put another dime in the pot." AND HE IMMEDIATELY FOLDED.
Now, if poker is not a PEOPLE GAME played with cards.....how could that happen? If it was simply playing the cards you were dealt, he would have bet again after the turn, and I would have folded my 10's, assuming I had been beat, and that would have been the end of the hand.
Another way to prove the "people" aspect of the game is to look at how emotions control the game. A person who lets emotions control their game is a player that will give you all their money. I can't tell you how many times I've taken advantage of players that are "on tilt" and gotten them to do things that didn't make sense, and they shouldn't have done. When a player is "on tilt", it means their emotions are controlling things instead of their brain. Be it anger, happiness, or whatever, emotions ruin a poker game.
This past Saturday night was a perfect example. One guy we play against folded three hands in a row that he would have won. He just kept whining about it. Finally, someone moved all in ahead of him, and he called with a very shaky hand (A-6 suited). Turns out he was up against Kings, and he lost the hand. So what made him call? Emotions. He had convinced himself that his other folds were wrong, and that his hands were unbeatable, and it cost him thousands of chips that he didn't need to waste. And honestly, knowing what he folded, his other folds were correct too.
I don't know how to teach you to stop letting emotions get in the way of good poker. You're just going to have to learn how to do that yourself. I say all the time "I don't tilt", but people don't believe me. However, I honestly believe that I don't. Some people think that EVERYONE tilts sometime....but I don't. There's just no reason to tilt. It is EXPENSIVE.
I say that, but I guarantee you the next time you suck out on the river to win a hand against me, and I raise preflop on the next hand, you're going to ask me if I'm on tilt. Heck, you're not even going to ask. You're just going to announce that I am. That's cool. Just call. Please.