If I squint I might see parallels with some of my own circumstances the last few years, but really the reason I've become fascinated with Robert Aldrich's The Killing of Sister George is Aldrich's supreme artistry with Frank Marcus's wonderful play.
As you see more of Aldrich's movies you come to appreciate the depth of his versatility and humanity. A number of his films verge on camp, or, like Whatever Happened to Baby Jane, revel in it, but what distinguishes even the most outlandish of them is a simple feeling underlying the shooting and the shouting; The Killing of Sister George is broad, coarse, and satiric, sometimes bitterly so, but it's also sensitive and affectionate, especially toward its flawed heroine. (Incidentally, the Killing trivia section on IMDB is especially good, about a 6.9 -- we learn that the girl-on-girl sex so disgusted longtime Aldrich collaborator composer Frank DeVol, he quit working on Aldrich's pictures. Good riddance -- the scene DeVol found so offensive plays effectively as the movie's climax, in part because Aldrich considers the two not as lesbians, per se, but as people.)
Its view of lesbian life is progressive but unblinkered, with a detachment once referred to as "adult." Beryl Reid's George/June exacting punishment from Childie/Alice (Susannah York) by forcing her to chew on her cigar (which Childie turns on her by making a show of relishing the filthy cheroot out of sheer perversity, which George takes as a bad omen) is a supreme metaphor for straight and gay marriage alike.
Visually The Killing is startling, presented for the most part with the magnitude and pacing of an action movie. At pivotal moments the frame is distinctively and cinematically suited to the poignant story at the film's heart. One thing that is almost uconsciously disturbing is how unattractive Susannah York is from the start: despite her natural, hyper-sexy gamine appeal, when she's introduced she seems awkward, puerile, and unphotogenic; during the extended scene when she and George go to the lesbian nightclub to perform to do a Laurel and Hardy bit, her face is covered in greasepaint, less reminiscent of Stan Laurel than plain ghastly.
If you think that actors talking about their "best side" are just being vain, watch your own image taken from various POVs in a video recording sometime. Or, just try to find a shot of Susannah York looking pretty in the first half of The Killing Of Sister George, fighting some harsh lighting and a succession of chiffon baby-doll nighties in a failing attempt not to look like a vapid duck