Traditional weddings

So I was talking to my mom a couple days ago about weddings, and the topic of traditional weddings came up. No matter what religion or race you are I feel like all weddings are mainly the same sort of thing. Big ceremony and then big reception. I really don't want to have that for my wedding. I'm currently dating my boyfriend for about 16 months now, and we talk about marriage like we're already married haha! We both want a very simple and close knit wedding, with just immediate and maybe a few extended family members. My only question is, what do you do if you don't want a certain member of your family coming? That sounds so rude, I know, but I'm sure we've all been there!