Visible crew/equipment: Dolly tracks are visible in Ian McKellen's house on the carpet.
Continuity mistake: Keep a close eye on Ian McKellen's picture in the newspaper. When the picture was taken, he was in bed and reclined; the picture in the newspaper has him standing, against a wall and holding a small paper with numbers on it mug shot style.
Answer: He didnt commit suicide in the book, he took his rifle to a fortified spot alongside a highway, and began shooting at cars. The police killed him. The film seems to tone down the story a lot, so I guess the only answer is they didn't really want to end it in such a violent way.
RJR99SS