2017-12-08: Since nobody got any further, I'll post some ideas I came up with.
Lazer's guess gave me a hunch to look for
eclipses. I have no idea why Lazer guessed sun-related events, but assuming there was a reason, an eclipse would fit the idea of travelling, being tired at the end of the day and at least a bit the theme of resurrection/reanimation.
and your hinting on a specific day, and mentioning that he would have been joking, had the appointment been a day earlier, gave me the hunch that this day might be
the 1st of April, thinking of April's Fools jokes. Which would make the appointed day the 2nd of April.
combining this, I looked for
eclipses on the 2nd of April. The only I could find will be 2117. But as I could not find any hint in the riddle that would make the exact 100 years offset click, and this specific eclipse would mainly be visible over the ocean near Australia, which would certainly fit being tired, but I can't detect any connection to the other four places.
As for your hint/question "What IS Frankenstein":
It's a novel. May substitute tale, fiction, story, literature or narrative. If you want to be a bit unprecise, you could also say it's a book.
And another thing. I'm getting confused with your wording. Sorry, I would have posted this as comment but lack the reputation to do so.
1) just to be clear: Since you very clearly state you already met your friend after you were supposed to meet and came back in time, I assume we talk about actual time-travel (in this hypothetical setting of the riddle) and not some date-line trickery. Do I assume correctly?
2) I assume the following sequence of events from my perspective and point in time:
1. point in time (what I would call now): you talk to me about the riddle
2. point in time: You are/were supposed to meet your friend
3. point in time: You will talk/have talked your friend after missing the actual appointment and he seems very tired and tells you that you "missed it"
4. point in time: You travelled back to 1. point in time.
Going by your wording of "At the end of the day, he was very tired and told me..." I further assume that 2 and 3 are on the same day.
Is that right?
3.) assuming 2. is right enough to let this still make sense: you say "Earlier today (when I was still in the future)"
Does that mean all points in time laid out in 2. are all on the same day.
Or did you just add the explanation to explain that you were supposed to meet earlier that day you come from, so points 2, 3 and 4 are on the same day but not necessarily 1, which might be a lot earlier?
Or does the today refer to the day that I call today but your appointment is still in my future, so the main point is that points 1, 2 and 3 are on the same day, but not necessarily 4.
Or is this all of nor real relevance? Or is the answer to this too much part of the puzzle?
4.) In the original text your friend said that you MUST have met, but in your hints you word it SHOULD've met. Big difference to me. Does it matter or can I go with "should"?
EDIT 2017-12-08: Oh, new hints just arrived ;-)
Commenting on your ultimate hints:
I can only find "Winged Death" with a direct relation to wings. If you are hinting towards a story with a winged creature in it (just in the story, not in the title) then we have an abundance of titles to check, as winged creatures or winged avatars are quite common in the Mythos. Might even be the rather famous Call of Cthulhu, since Great Cthulhu also has wings, although this is definitely not its most prominent quality and no-one who witnesses his presence cares whether he spreads them or not.
(edit 2018-12-15, because Gareth is right and my memory faulty:)
I just read the story again and there is no winged creature in The Music of Erich Zann. I have no idea from which depths of insanity my mind sprung that up.
Commenting on ultimate hint "Dublin":
Thanks, I needed that hint, wouldn't have found her on my own. Still at a loss about the particular title this is about. Breathe would fit to needing some fresh air, but I can't find something about wife or bride or similar.
Commenting on ultimate hint "hint from your comments"
I don't find myself in need of a preposition to answer that. Did you by chance mean adjective or prefix, or really preposition? Also, did we agree that Frankenstein is synonymous for Frankenstein's monster? In that case, a might add creature, fictional, monster or one of horrible, horrifying, horrific, ect to the list that maybe enlightens one of my fellow solvers.
I'll keep thinking about it.
EDIT 2017-12-13, more thoughts:
I am still wondering why the text explicitly states to meet your friend in Ketchum, and then asks where to meet them. So I assume the line about Ketchum codes the hint for the exact location. But if so, you would probably not be able to catch your friend in Dublin, so why phrase it like that? Anyone has an idea on this?
Might have a new lead on Dublin here:
If "remember your wife" is a hint to the story, and it's not meant to be obvious from the title but relates to the content (as for instance with Frankenstein), then I'd suggest "We Come Apart" as the title of choice here. As far as I managed to skim the summaries, it's the only book clearly about the topic of marriage and wives.
And here is another approach I cancelled, but would like to mention in case it's not so bad as I think:
The overall theme of returning from the dead gave me the idea to check for christian Easter ceremonies. Would also fit meeting at the toll of a bell (no match for Dublin though). Also I was looking for a public, open air ceremony, since the friend needs some fresh air. My current fixation on 2nd of April though doesn't add up, as resurrection day will be Sunday 1st of April 2018.
As for why I am fixated to look for a certain date at the moment:
The date comes from the hint that the friend would have been joking if they were to meet one day earlier, and for the time being I can only think of April 1st as an answer to that hint, so if that's right, the meeting was (or will be) scheduled on a 2nd of April. With nothing else to go by, it would be reasonable to assume the year is the next one, which is 2018.
And just for fun:
There is a group in Germany that does Horror Diners. They had Dr. Frankenstein, trying to create yet another monster (nice match on Bournemouth, one show was in actual castle Falkenstein btw), Dracula, looking for a new bride (nice match on Dublin, although contradicting OP's hint about the author there), and of course each diner starts at the chime of a bell (meet me at...). No real match for Rhode Island, though, but this one just has too many winged creatures in his stories to be sure about that anyway.
Apart from suspecting OP wouldn't know the guys nor make up a riddle for such a small event, the present show is Jack the Ripper and none will take place on 2nd of April. So no match, but for a few minutes after I started reading their Web site it really looked good :-)
EDIT 2017-12-14. (deleted due to Gareth's note that it was a false lead)