Sounds very much like you are seeking drama.
Firstly deciding whether or not to attend and event because of the perceived slight of not being invited early enough, rather than making the decision on whether you want to go or not.
Then starting a thread with little information about the situation and refusing to add any (your prerogative) but then getting annoyed when people are assuming things. It's just attention seeking. Like when people post of Facebook "I'm so angry" with no context, hoping people will chime in with "You alright hun?"
YABVU.
I very much enjoyed a wedding where we had a phone call on the evening of the night before asking us if we'd like to go as someone else was ill. We were free, and liked the couple, and their family, why wouldn't we go ??