I can watch movies for hours but only alone. What said FlameKeeper is very relevant.
But if I have to watch a movie with someone else (or eventually a group of people) it's getting chaotic. I just can't focus for long, I need pauses often, which is impossible to beg for when I'm watching a movie with a group, so I need to find another way to "escape", and that way to escape can be : doing something else at the same time, for example play with my phone, read something on the net, answer a message... Of course I will miss some parts of the movie but at least I can continue to watch it till the end. I will also be seen like being impolite or geekish but no matter !
Sometimes when I watch a movie with only one person (friend or family) I just fall asleep after 30 minutes and wake up at the end of the movie... Frustrating !
I also usually don't go to the cinema, I don't like the fact that we have to sit still, I just feel like a prisoner. But if a movie really interests me, I will make an effort but I swear, I watch my phone very often to check what time it is, I always need to take 5 minutes break after approximately an hour of the movie.
One of my friends is pretty frustrated about my problem because he knows I can watch movies for 3-4 hours if I want, but alone. He would love to be able to see a movie without interruptions or without me falling asleep but that's it, that's how I function...
Well at least, now I can tell him why I have that problem, positive point ! 