The movie is self-indulgent and, despite some seriously good acting on the part of Vanessa Redgrave, looks silly and shoddily put together, devoid of a tight mesh of character and story complexities which give a movie its edge and relevance. Madeleine Potter as Verena Tarrant seems offers a limited range of facial expressions, mostly talking with an affected pout, watching with an irritatingly faux-innocent face the comings-on of Olive, and throwing herself now and then into the passion of a kiss or -- I think there was also a scene or two to that effect -- a fit of crying.
That being said, while the arc of the story seems rather too simple, the character of Verena is more complex than it appears. She seems moved by a desire to please others to such an extent that you begin to wonder in what aspects of her behavior are an expression of her being true to herself, and how conflicted she is about making certain choices. She seems so out of touch with her real feelings at times, than when she does express passion, it comes as a surprise. It's an interesting character, even though it's not developed enough in the context of narrative events.
I would say the movie is worth watching for Verena's psychological make-up -- her opaque acting, now that I think of it, might be a plus -- as well as for Vanessa Redgrave's performance as a repressed, intense old maid. Also worthy of note are Jessica Tandy and Linda Hunt.