A lot of this movie is ambiguous, right down to the end. So a lot of the "Yes" answers on this site refer to things that are implied or shown on screen but that may not actually have happened.
(Huge spoiler). The main character is mentally ill and suffers psychosis and in this state she beats her husband, almost kills him and then accidentally kills him.
There is, however, a scene where the camera moves at different angles as characters are standing on a swing. One of them appears to have motion sickness, and the scene might cause the same.