Or do I not understand fully what it's like to be a BS.
Understatement. Of the century.
I responded to your other thread. This shit is hard. Of course you're afraid, of course you're sad. Sometimes, you might even feel angry. Those are normal, understandable post-DDay feelings, and we've all BTDT. The important thing is, to make certain you identify the origin of all of those emotions (you), and place the blame accordingly (also you). Your feelings are every bit as valid as any other human's, and you have every right to feel sad.
There's a big light bulb hanging over my head and I'm strapped to a chair and I'm being interrogated.
You don't have to submit to that torture! You have a choice. Pack a bag and GTFO. But if you're planning to stick around, the drama queen act is not helping your case.
Why would she want the sordid bits to stab her in the heart and to replay over and over?
You don't have to understand why she wants it. You don't have to understand, or even agree with, what she's saying and feeling. If she agrees to R, and you accept that gift, all you need to do is *whatever she asks.* Even (especially) if you're afraid it's going to make her leave you.
Good luck, I know it may not seem like it at first, but the WS here are rooting for you. Because, a month, or a year, or a decade ago...we *were* you.