Friends and Poker

To stack or not to stack your friend. If you are in a game at the same table with a good friend and you have the nuts and he shoves ahead of you, do you call? If you say anything but a loud "Of Course!!!" then I suggest you evaluate why you are playing. Are you playing to win or are you playing for entertainment only. If it's entertainment only then I can maybe sort of understand a decision not to stack a friend, but if you're playing for profit you have to do it.
I suggest if you are going to play with a friend that doesn't know that you will beat them if you get a chance that you set that straight ahead of time.
What if two friends get in a big hand against each other? I suggest wishing them both luck or staying out of it. You don't want one of them to get their feelings hurt over something as simple as that. You can privately congratulate the winner later as well as console the loser. Don't get caught up in the heat of the moment and say something you will regret later.
I try my best to always be a gracious winner and loser and I think I do a good job of not being obnoxious or a whiner. Manage your money well and don't get yourself in a game you can't afford and it makes it a lot easier to control your emotions. I grew up playing all types of games. I love winning but I don't rub it in some ones face if they get lucky and beat me once. I make a note of the hand for future profit. Get excited if someone you play with often lays a bad beat on you; that means you should get plenty of chances to let the odds work in your favor against them. Play enough hands with them and the odds will come to the surface of the statistics so get excited, not mad.