Lean On Pete (2017 Andrew Haigh & scr)

Yes, didn't like 45 Years,  did like this - adapted from Willy Vlautin's novel. Charlie Plummer (no relation) grows to care for Steve Buscemi's horse of the title. Chloe Sevigny and Steve Zahn (when he does finally appear an hour and a half in) are no help, but there's a kindly aunt (Alison Elliott) on the horizon.