Odd, unique, and surprising
I did enjoy the plot of this story - something I've never read before, to say the least! And it truly surprised me, from one paragraph to the next. I certainly didn't see the ending coming. (Very Judith & Holfernes!) The most sympathetic character, for sure, is the Rabbi, although his wife ends up being the hero in her own right. For a short story, it gave enough detail to understand the characters, but I wish I knew them better - especially her, before she makes her dramatic decision.
Read the story now
Also, as an erotica fan, I need to get some really good description, a slow burn, and enough heat to get me going. (At least, that's the stated goal of most erotica!) The sex scene here felt... weird. I was uncomfortable, and that's not hot.
If the author decides to cut the sex scene, or make it smoother and more literary, it might work. Or, he might choose to really spice it up and give us readers some more panting, tense, soul-rending emotion (and sex) that would elevate it into the realm of the believable. Perhaps that would involve some more planning and reflection on the lady's part, though.... good erotica needs heavy build-up.