Films about being isolated

I Am Legend
I Am Mother

The Shinning (1980)

Isolated in what sense? Isolated from the world, isolated from the people, isolated from oneself, isolated from one's surroundings, mental isolation, isolation in a room or a basement. One may consider a movie like The Ring to be about isolation of a girl false diagnosed as possessed by an evil female spirit who was in isolation for centuries, then the girl victim herself became isolated from the world, again, permanently, in her afterlife.

Arctic - Intense movie.

Alien. They are stuck on a spaceship with a killer space alien.

THE ROAD.

Can You ever Forgive Me

Last Man on Earth