The last time I was embarrassed to be seen with someone, my age ended in --TEEN. I would hope that people would eventually outgrow that. Presuming your "friend" is older than his pubescent years, I would say that his mental age has a little catching up to do.

I'm truly sorry that your evening ended badly (well, ended before it even began) and I wish I were in your part of the world so I could assist in organizing a kilt night.