1) Have you ever cried while in character during a role-playing game?
2) Ever yelled/screamed at someone else in character? If so, did you feel you were actually angry, or just playing a part?
3) If you answered yes to either of the above, was it more cathartic, or upsetting? How did other people react? Did you continue to enjoy/participate in that game?
4) Have you ever found yourself experiencing your character's feelings for another character as YOUR feelings for that character's player?
5) Have you ever gotten into an out-of-game fight (verbal or physical) with someone as a result of something that happened in a game?
6) Have you ever lost a friend specifically over something that happened between characters in a role-playing game?
For the record, I realize that if you get upset at something that happens in-game and you cry or yell or what-have-you, there's an increasingly thin line between whether that's you, or your character. I'd say the dividing line is whether you continue to role-play while you're crying (or as soon as you can talk again), and whether you keep the yelling entirely in-character – that is, whether you channel the emotion into the game, or drop character to deal with it.