In continental USA

We're not actually not invited it's just an old friend we used to work with and we saw on Facebook the date and place she is getting married the way I see it that means anyone is invited. She's not the kind of person to have a fancy wedding and I expect it to be very casual and my friends said they are going to dress casual but I plan on wearing are suit because if you're are going to crash are wedding you should at least look nice. But I know my friends are gonna give me hell for dressing up. What should I do? We're all are a bunch of immature 22 year olds if that makes are a difference. You guys are a bunch of asshats. I'm going to this wedding. We are not on bad terms we are just out of touch and she posted it on Facebook. If she wanted a secret wedding she shouldn't have told the world the date time and place. If we are asked to leave we will but she likes us and she would never do that. I don't see the problem.

Diamond rings are appealing but i feel its more just of a engage/promise kind of thing.. i know someone who wears a diamond ring on the left hand, but fourth finger and isnt engaged or married and always thought diamond rings are for married or engaged.