Five essential characters/story lines I will attempt to tackle. Because, well, I HAVE TO in order to feel as if this chapter (if not the entire book) on TWIN PEAKS has been closed. Here are some of my takeaways on what happened regarding these five characters & most important elements of THE RETURN in my opinion (and I would LOVE to hear your theories!):

1. AUDREY:
Audrey was not in a "coma" per se, but a fugue state induced by BOB following the rape in the hospital. BOB's intention was to procreate for an evil earthly lineage. Let's face it -  Audrey Horne would be the LAST person anyone would want to deal with, especially BOB while their offspring was alive. Because BOB was responsible for putting Audrey in this state, Audrey experienced her own version of an alternate timeline - they weren't wild dreams of being in a world still connected to Twin Peaks, it was her existence in this trance. It was an altered/alternate Twin Peaks to her, the REAL Twin Peaks being out of her reach (hence she couldn't cross the "threshold" to snap out of it). Much like Dale & Diane becoming "Richard & Linda" - or Laura becoming "Carrie" - Audrey's version of alternate life (a la Odessa Texas for Dale & Laura) had very familiar feelings & people attached to those feelings but with different names (Billy, Tina, etc.). These must be people we know from Twin Peaks - but only Audrey knows which names are attached to which people (I think the introduction of "Eddie Louis Severson" at the Roadhouse, when we ALL know him as Eddie Vedder was a huge clue).

When Richard Horne was zapped by Mr. C, the spell was broken - Audrey was then allowed to wake up from her fugue state / alternate reality because she no longer posed a threat to Mr. C.
The white room, brightness, lack of makeup and "sterile" feel of her surroundings leads me to infer she was in a hospital or institution, and had no idea what she had been doing all this time.

2. SARAH PALMER:
- Sarah was the girl inhabited by the frog-moth creature back in 1956
- The frog-moth was a primitive, less advanced offspring of "MOTHER", and that offspring of "MOTHER" has lived inside of Sarah ever since
- It took decades for this primitive offspring of "Mother" to develop & mature, so Sarah Palmer changed and became more evil & more powerful as the "offspring" matured
- The reason Leland (BOB) had to keep Sarah drugged all the time was because he KNEW Sarah was inhabited by MOTHER'S offspring - and did not want it to interfere with his evil doings
- In a nutshell, MOTHER'S son (BOB/Leland) was married to MOTHER'S daughter (Sarah) in a quasi-incestuous relationship - and brother kept sister in the dark through intoxication and drugging.

As for the end of THE RETURN, "Sister" is finally mature and ready to wreak havoc on the world. Sensing something had been altered when Cooper went back in time and saved Laura from death. "Sister" came to the realization that everything she'd been through in her life was for nothing - the drugging, the intoxication, having to wait until she was ready for "her turn", the effort to "put on a face" as it were for the "human world". I don't think she was disturbed by Cooper's action in saving Laura from death at the hands of her "brother" - instead, I think "sister" was disturbed that her bother BOB had his chance and she doesn't - and in the end, she's wasted her life waiting for a moment that will never come.

3. THE FIREMAN:
This message was delivered to Cooper JUST BEFORE HE WAKES UP from his coma in the Hospital
"Listen to the sounds" - this is what you'll hear when you're at the JUDY threshold...
"It is in our house now" - JUDY is now accessible to Dale, and it' will be a part of Dale's/the Fireman's bigger plans going forward.
"It cannot all be said aloud now" - Dale will need to find out for himself what JUDY is.
"Remember... 430... Richard & Linda... two birds with one stone" - The Fireman is asking Dale to REMEMBER (1) how to get to JUDY, (2) who he and Diane will become once they reach JUDY, and (3) what he told Gordon Cole 25 years earlier about "doing whatever it takes to find him" - because Cooper must change that request and tell Gordon NOT TO FIND HIM (which he does as he opens the basement door at the Great Northern).

4. DALE COOPER:
"Richard & Linda"
I believe that OUR Dale Cooper left Diane in the car and walked into the Motel office - but it was not our Dale who walked back out and beckoned Diane to enter room 7. It was "Richard".
Diane was Diane while having sex with "Richard". Diane began to feel it wasn't Dale, which is why she was so uncomfortable with him in bed and began covering his face. It may have been memories of the rape by Mr. C 20+ years earlier, but more a realization that she too would be changing, and began to understand why she saw "herself" standing outside of the Motel office. She saw herself as this other person - "Linda" - waiting outside for "Richard". She couldn't face this reality and left during the night.

By crossing over to this new dimension (which I believe is JUDY) he's now part Dale, part Mr. C and part Dougie. All of the different iterations of his "being" and existence are with him, and if Cooper continues to travel through different dimensions/alternate realities he will continue to take those characteristics with him (while probably gaining new ones). This is why he could be a cold, calculated bad-ass at the Judy Diner (like Mr. C), seem completely distant and in his own world while driving to Twin Peaks w/ Carrie (Dougie) and still have the sense of duty to reunite Laura with her mother (Dale) all at the same time.

Cooper's intuition, strong existential nature and philosophical mind made the transition to "Richard" more complex - it allowed him to retain and experience prior iterations of his existence, which is why he hadn't fully embraced being "Richard" by the final scene. He was essentially "fighting off" becoming this new identity of Richard without even realizing it.

5. LAURA PALMER:
Laura has already experienced the same thing as Dale, having been pulled from Twin Peaks and escaping death 25 years earlier - and has been living in her new alternate reality as "Carrie" for that amount of time. As time has passed, her memory of & identity with "Laura" has faded away. "Carrie" is the identity she embodies; she's not as intuitive or strong-minded as Dale, and she's psychologically distanced herself from the horrible experiences & memories of being Laura (she WANTED to forget - Cooper DOESN'T want to forget).

THE FINAL SCENE:
When Dale arrives with Carrie at the Palmer's house, he's asking direct questions (like Cooper would) but can't understand the answers he's getting (like Dougie would) and has this innate feeling that the confusion & evil he's sensing is both proper and right (like Mr. C would). As we see moments before the final curtain, he's still able to figure out something's wrong, but is pulled in different directions and cannot lock in on the answer. Even the home owners names of "Tremond/Chalfont" should have raised a red flag for the old Cooper, but now...

It's Carrie who has no clue who she really is or what she's feeling - but thanks to the presence of the Mrs. Tremond/Chalfont (who has always been sort of the "guide" pushing Laura in the direction she wanted her to head) - she hears the voice of Sarah calling out for her - then it all comes rushing back in a terrifying memory of her true self.

Well, glad I got that off my chest & thanks for reading (if you made it this far!) - I'd love to read what your take is on this.