dear alison,

• Did he go back in time to kill himself? No. He was sent back in time in a sort of paradoxical loop. Knowing everything that was going to happen (with the airplane falling through his room) he could have saved himself, but he chose not to under the assumption that he could "take away all those moments of sadness and replace them with something better."
• Or did he go forward in time? No. Frank saved him the first time and he continued on an alternate time line in which he did not die. He was subsequently sent backwards "when the world ended."
• Was frank a real person dressed up as a bunny the whole time? Yes. You remember in the movie theater when Frank said how sorry he was? It was for killing the girlfriend. He was the one driving the car. He was a real person from Donnie's future (the one in which he survived), and he is the paradoxical point in the time line.
• Did frank travel back/forward in time? Frank traveled backwards.
• What did grandma death have to do with anything? He never even talked to her! Yes he did - just once. She told him "every living creature dies alone." She is arguably the most important person in the whole movie, since she is the one who first uncovered the true theory of time travel. The real question is: did she suffer from a similar paradox and survive, or is this what would become of Donnie if he survived?
• The two teachers: were they in on it too? No, but the were the only open minded people in Middlesex. They were Donnie's confidants - the only people he really trusts.
• I'm not sure I understand what Swayze's part in the movie was either. Was he really some sort of antichrist? No, he was not the antichrist. It was more to prove that what Donnie did in these fits wasn't really bad. It was also part of the paradox. If Donnie didn't burn down his house, Patrick wouldn't have been arrested. If he wasn't arrested, Donnie's mother wouldn't have been on the plane that crashed through his room. If she wasn't on the plane, Donnie wouldn't have gone out to Grandma Death's house that night. None of this would have happened.
• "Conscience" and "Arkansas": why?! WTF? I don't understand the question.