?? Possibly 'Ritual'..??

S.O.S.!!!

I need the name of a short film I saw when I was about 15, so that would have been approximately 25 years ago, around 1984.

Here's the plot....Well, what I can remember of it:
A young (let’s say 25 -30 year old) couple are chatting cordially. There is a feeling of normalcy and peacefulness in the scene. He gets dressed and goes off to work, and the woman is now free to act according to her own thoughts, as well as her impulses.
She goes to the kitchen and takes out at least one large knife.
She strips down to either a very skimpy outfit or perhaps nude (I can’t recall). She moves the bed into the living room, right next to the front door. (They live in an apartment) She somehow attaches the large knife to her abdomen. It is angled toward the door, blade side pointing to her stomach, handle wedged to door perpendicularly. She hears her neighbors moving about and talking. This seems to excite her. We can tell that she is very anticipatory. She stays in that position for quite a while. She wants to be discovered via someone coming into the apartment – and by doing so, causing the knife to penetrate her. She is sweating quite a lot b/c of the danger element. She wants her husband to come home and be the one to open and stab. Crucially (and I do hope this is correct), the only other thing she does is to pack it all in, get the bed away, and takes a shower, as nobody opened the door. The title, if I recall correctly, is called “Ritual”, which makes this alarming discovery that this is a routine the wife performs on a daily basis. CREEPY!

<<< I am vague about some of the details, including the title, but I think this is a fair representation, so hopefully someone out there has seen it. >>>

Thanks in advance!!!