To critique anything, you must first have a previously established and pertinent example or examples of something that came before treading the same ground to provide a baseline.
“I'm thinking about ending things” has only stylistic cues from which to base a critique. Due to the lack of a baseline in which to provide proper orientation, narratively speaking, this movie plays more like experiencing something foreign first hand than a typical cinematic experience.
I for one loved it, you may or may not. Either way, It is truly an achievement in deconstructing, reconstructing and re-deconstructing reality.