I feel your pain.

Years ago I threw a party for work friends and acquaintances where I had 30 confirmed and 10 tentative (from calendar invite). I bought a variety of drinks (alcoholic and non) and bought/cooked food for about 50 to ensure there was plenty.

… 4 people showed up.

That was the instant that I stopped giving a fuck. Ever since then I’ve adopted the approach of “I’m going to do something, you can come if you want, but I’m not planning for you”. Or, more commonly, I just don’t organize anything :)