I Go To Funerals (1971)

Young adult Harold Chasen, solitary and friendless by choice, is obsessed with death, this fascination manifesting itself in he staging his own fake suicides, driving a hearse and attending funerals, even of people he doesn't know, all to the chagrin of his exasperated wealthy mother with whom he lives. Mrs. Chasen is determined for Harold to be "normal", including her sending him into therapy to deal with his issues and finding him a girlfriend through a computer dating service. It is at a series of funerals that Harold meets Maude, on the cusp of her eightieth birthday, she who too attends funerals of strangers. Unlike Harold, Maude is obsessed with life - her own life to be more precise - she does whatever she wants to please herself, damned what others may think or how they may be affected.
Ruth Gordon, Bud Cort, Vivian Pickles