To be a little annoyed when you take the time to help someone and they don't even respond?

[FlamingoBingo]

Someone CATed me a while ago to ask me something and I sent them a really, really long email in response, trying to be as helpful as possible, and I got no reply at all! Tried contacting them to see if they got it, but no response.

AIBU to be a bit miffed?

That is annoying, YANBU. It wouldn't take them long to email a quick thank you!

I wonder if that was the same person that contacted me?!

YANBU I think I would be miffed too.
I often live in perpetual fear of being the perpetrator of something like this. Anything involving not returning FB messages, texts, phonecalls, emails... because I know how I would feel if someone ignored me for a few days.

That said, I was a sensitive child, that teachers promised my mother I would grow out of. They were wrong.

It could be that your e-mail is in a junk folder they don't even realise they have as this has happened to me. I have two junk e-mail folders, the one called junk and the one called McAfee security something or other. I get an alert that an e-mail has gone into the first one but I have to remember to check the second one regularly.

Apart than that, I can see why you feel a bit miffed.

Hopefully that's it, Simply.

I don't bear grudges, so won't be avoiding her posts or anything, I'm just surprised and a bit annoyed I put so much time into replying!

I would be very miffed.

But that would mean two emails lost to the same person, as I did follow up to check she got it, and that is too much of a coincidence? Asked on here too.

YANBU, it is rude. But some people are just like that, sadly - it's the slow dying of manners. I (partially) blame kids' tv - no one ever seems to have any manners on kids' shows.