Basically as the title reads for one of my friends wedding. We are in our mid 30's and whilst I'll of course be there, I can't help but feel sending them this early is a tad ridiculous! I know she's excited but every convo is about the wedding and going venue searching and it all seems odd to be for a wedding nearly 3 years away 
Having said that I did get engaged to married in less than 12 months which I know isn't the norm.
YABU - she's just excited
YANBU - its way too early!