other peoples anxieties

someone I know was invited to go to a wedding, of one of their friends children. my friend didn't want to go because of the amount of people there, and would say things like "I don't like those sorts of things", and would get quite anxious when I would mention it.

Hi EP!

Then your friend cannot easily adjust to being in crowds of people. More, people he/she may know.
Your friend is afraid of being among people she/he neither, trusts nor feels secure amid.
The way you may feel among others is so far away from his/hers, I feel you should never, out of friendship alone, invite your friend to such events again.

What you are doing will cost you your friendship, for it is far less valuable than a person's own self-awareness of fear.

Excuse my rude exit, but I am hurried!

Kind regards!
Mark...