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The twist-ending plot sounds similar to something from "Night Gallery" or "Alfred Hitchcock Prsents". The latter had a reboot in the 80s or 90s which were in color and had used old openings with Hitchcock that had been colorized.
Another possibility might be something from "Tales from the Crypt Keeper" which was on in that period. When you say she "lost her marbles", did she mentally revert to babyhood after seeing the ghost? That would tie in with the "born again" comment and be the type of humor that show liked.

This is SO random but it has been bugging me since I was a teenager, and I'm now 37, and I *know* I watched this, but I can't remember what the heck show it is from, and I've searched everywhere, so I thought I'd throw a hail mary here.
Info about the show:
1) It would have aired in 1996-1998 (think it was 1997 but can't remember exactly, all I remember is I watched it in an apartment that we only lived in for those 2 years).
2) It would have been on one of the major broadcast TV networks (so CBS, NBC, ABC, UPN, or WPIX/WB at the time) because I didn't have cable TV in my room.
3) It was later at night, either during the 10 PM programming or past the 11 o'clock news because I remember I had to be up for school in the morning and I shouldn't have still been awake but the episode freaked me out so much that I had to watch the whole thing.
4) It was NOT a sitcom, and I don't think it was something like Homicide: Life on the Streets or Diagnosis Murder or anything because I seem to remember there being a paranormal element to it. I think it was something like Unsolved Mysteries or a similar "weird but true" kind of show with reenactments. I checked the TV lineup from the time and couldn't find anything that rang true, so it might have even been a TV movie or miniseries or something.
So, here's what I remember about the episode:
1) It featured an old rich lady (think Dynasty type with pearls, furs, etc., really over the top) who was incredibly verbally abusive to her maid/housekeeper OR live-in nurse (can't remember which). She treated her like absolute garbage, the type of person who would go "oops" and throw a glass on the floor just to watch her clean it up, etc.
2) The maid/housekeeper/nurse was a white woman in her 20s-30s. She had a boyfriend who was a typical "goon" type character, all brawn and no brains. I feel like he worked for the mob as like an underling or something but I can't totally remember. There is a scene where they talk about killing the old lady and stealing all her money.
3) Not too long into the episode, this comes to pass and they kill the old lady. I forgot how they do it, but I think she overdosed her on medication or smothered her with a pillow; I don't think it was a violent death because they thought the cops would think it was natural causes, and they would get away with it.
3) It turned out that she was the sole beneficiary of the woman's entire estate, so she ended up getting massively rich.
4) Towards the end of the episode there is a scene where she's all dressed up in the lady's pearls, furs, eveningwear type stuff and her and the boyfriend go "out on the town" in a limo and get totally drunk. They come back to the mansion and stumble out of the limo, and I remember this VERY CLEARLY — the maid/housekeeper/nurse was a TERRIBLE actress and acted "drunk" really stupidly and she kept shouting at no one "I FEEL LIKE I'VE BEEN BORN AGAIN! I'M BORN AGAIN!" It was soooo dumb that it really stands out in my mind.
5) So they go back into the mansion and proceed to start making out in the old lady's bed (I don't think it was anything too explicit but they were obviously going there), and at one point the maid/housekeeper/nurse looks over the dude's shoulder and sees the ghost of the old lady in the corner of the room, watching her, and she had that really like stereotypical "ghost" look (think the Casper movie) where they're like vaguely glowing that white-blue color. It was a sting/jumpscare moment that freaked me the hell out.
6) I don't super remember what happens after that, but I think eventually the maid/housekeeper/nurse goes crazy and ends up confessing to the police or gets caught somehow.
SOMEONE TELL ME I'M NOT MAKING THIS UP AND THIS REALLY AIRED ON TV! It's been driving me crazy for like 20 years!
TL;DR: 80s rerun or 90s new episode of Unsolved Mysteries type reenactment show where a maid or nurse kills a mean old rich lady, inherits her estate, gets drunk with her boyfriend, screams "I'M BORN AGAIN!" and then sees the ghost of the dead lady and totally loses her marbles.