Persona 3, after climbing the tower for around 15 floors or so for the past 2 hours, i meet an enemy, it uses mudo, kills the main character instantly and i get a game over, quit for 1 month just because of how BS it was.

Majora's Mask: Was doing snowhead temple and was about to get to the boss, game freezes up and because of how stupid the save system works in that game, i lost about 5-6 hours of progress. Quit the game for 2+ years and just recently came back to it.

And some other stuff when i was dumb kid.

God of War God Mode playthrough. The last room before you get Pandora's Box. There's harpies which do an unblockable fireball attack, archers with exploding arrows that stick to surfaces, a floor made of conveyor belts that go into steam rollers on the side, and the only platforms to escape that motion will kill you in 1 hit with flame if you stay on too long. Oh and did I mention I had used all my magic on the previous group of enemies because I ASSUMED I would get magic and health before that room since I remembered it being the hardest in the game. I failed easily over 50 times before FINALLY beating it which had me screaming and crying before finally beating it and crying tears of joy. Many a pillow was punched that day in rage. The rest of the game seemed SOOOOO easy and I had to laugh when people said the Trial of Archimedes was giving them trouble in Ascension. Even Ares and the clones just seemed like a cakewalk.

I'm pretty sure it didn't.  I hope that's the case.  During the Nes days, if a game had an end, I made it my mission to earn it if I ever played it.  I don't remember ever beating that game.

Awesome game but like the rest of the Nes games, if you jumped, you were comitted to that jump.  You couldn't change direction in mid air (unless you used Grant DaNasty--called Grand Dynasty by me and my brother) leading to a bunch of frustrating moments.

Watching Fraser Agar play Beyond

When I was around 9 or 10 I was playing the last boss in Final Final Fantasy X-2 and died about 200 times. I didn't really do anything violent in response but I remember running outside early in the morning jumping around when I beat it.

When I was playing "Beyond the beyond" (PS1) the random encounter was so frequent that I just threw the controller down and never played the game again. Even when I finally got a Codebreaker, I didn't feel like playing the game anymore.

The last storyline boss or the last Via Infinito boss?

Anytime I died playing Halo 2 online

The storyline boss (That was a big deal for me) although now I'm sure I wouldn't have any trouble with beating it again.