Spontaneously invited a friend over for a slap up dinner because I knew his wife was absent over the WE. Slightly pissed off that he didn’t respond at all and at the same time, secretly relieved that his falling asleep on the sofa as usual after eating wasn’t an issue I would have to deal with.

To answer the header: no, you are not

Don't be annoyed with him for not responding, his wife was away so he was clearly busy with the mistress.

Strange post. Reads like you were trying to get him in the sack, but are not quite sure if you should, because you think that would make you a really bad person.

Now you can't get him out of your head and are making weird posts on internet forums.

?

Yes you are. But aren't we all?

A crush.

LOL I kind of thought similar but your post was worded far more amusingly than I would have managed.

Oooh, you got me there! Never thought of that - all I did was rehearse refuting allegations of what his wife and I were normally up to while he was asleep

This seems to really bug you, so why don't you tell him?

Roofies? Ye, you are bad!

or put some eye shadow on him.

There's your answer for him not coming.
He knows about your activities with his wife and as she's absent he knew he wouldn't get a decent sleep on your couch.

I had hoped for some free advice on trypanosomiasis for my friend. Instead I had to deal with most comments ranging from merely snide to explicit innuendo.
Unfortunately, this has increased my mental turmoil (I wanted to be nice and was actually glad I didn’t have to follow through) and I was wondering whether anyone could recommend a life coach fluent in both Swahili and Serbo-Croatian?

Okay, to answer your original question: No. Why?
You go with the flow .... you do something nice spontaneously, you are perfectly entitled to be annoyed that it's simply ignored. You see the good thing in the end-result.
Your life sorts itself out, can't you see? You don't need a life coach - albeit learning Swahili or Serbo-Croation (specially the latter could be of use to you, should you move to Thurgau or St. Gallen ) is never a bad idea.

Oh and thanks for teaching me the word trypanosomiasis.

Yes, you are. IMO. Don't do "charity" invitations. Is he your "charity case" or something? Perhaps that's why he couldn't be bothered to respond.

I invite only people I really want to invite and wouldn't feel relieved if they declined or ignored my invitation. And I would never accept charity anything.

looked it up myself
Any language is an improvement to TG-dialect

Thanks for your response – the non-acceptance of charity is strong in this one!
My dilemma had nothing to do with charity – was just trying to be nice, once in a while. I’d leave it at this but will now have to live with your mark of Cain* for a while…

*bad/good?