Allright, I'll admit, i was kicked out of one gaming group.
THe DM was a dear, close, personal friend of mine. but her game was so roleplay heavy... argh.
A brief overview. We worked for an immortal sorceress. Our Enemy was an immortal sorceress, hat happened to be our immortal sorceres's twin sister. Neither one detected as being evil, so half the time, we were running around on missions from the evil one, which, for some reason our (portrayed as) omnescent patron never stopped. We pissed off a LOT of people by stealing holy artifacts from the churches (she made up all the churches in the game, had her personal religious views reflected.) and nearly every encounter involved fighting our evil opposites (who were NOT clones).
We had to put up with countless NPC's that were far, far, FAR more interesting than we were or could ever be (The bartender was the runaway son of an evil archmage, who had a stepsister that was really a gold dragoness being kept in line by a collar that changed her shape AND left her with amnesia relating to her life before the collar, oh, he was also the homosexual lover of the fey prince, son of Oberon, yadda yadda yadda).
One day, i was sick of it. The Paladin had died at the hands of an dark (not drow! she homebrewed the races too) elven ranger with favored enemy: elves. When he passed on, we lost a great fighter, but were still saddled with his 12 year-old squire (TWELVE! But he was played by the GM more like he was four. Spoke in single-word meek sentences, broke out crying every time anyone but the paladin talked to him (sometimes even when the paladin talked to him) WAY too young.) and we were saddled with him. We had been tossed into a pit fight against "She's just misunderstood" Evil cleric of death that we had defeated, killed, and decapitated earlier in the game, but we didn't actually get to fight since the GM's OTHER pet NPC (A schizophrenic pacifist prince / serial rapist side-that-we-had-expelled) plunged the entire arena into magical darkness (how a rogue class character could do that, i will never know) and resuced us by hitting us all with a DC-21/27 (estimate, i was the only one to pass the Fortitude save with a 28, but my followup 20 failed) knockout shot. He then drtagged us to the surface and told us that we owed his very, very evil serial killer / rapist half our lives.
The GM's boyfriend (who had played the paladin) was now playing an incarnum user (The ultra-lawful kind) Who trusted the 12 year-old kid over my monk. I was sick of the whole thing.
I think the first sign that I should have just left was when the GM ruled that my character had been acting too chaoticly, and gave me an alignment drift from lawful neutral to pure neutral, and she ruled that I lost most of my monk special abilities (ki strike, stunning fist) I was reduced to being... a mildly effective meleeist. Even with good stats, i couldn't compete with the Incarnum user, who was doing better damage at range than I could ever hope to do in melee.
On top of that, she gave me with a cursed Monk's belt (which did -4 levels of monk, dropping me down to being a ECL 2 character).
It ended when I had a straight up In-character argument with the GM's boyfriend (who also happens to be one of the players for whom i have the most respect for in the world) where wy Monk ended with "If you don't trust me, perhaps we should not travel together!"
The GM ended the session there (an hour early) and told me it was probably best if I didn't come back. i agreed. We saw each other again on friday, where she and I were both players in her boyfriend's game

we're all still friends. her game kept running even after I left, and I actually became a kind of peer-review friend. she's very talented as an artist, but her stories make my head swim, they are so complex and favor tragic evil people.