Upset over this

Okay so today is my fiancés sister birthday. I personally have never met her in person but we've always texted, and also communicated over social media. I feel like every single time he has a family thing, I NEVER GET asked if I want to go, whether I want to or not .. I NEVER GET ASKED. His aunt recently invited me to one of his cousins birthday parties that I will be attending. However whenever it comes to me, I invite him everywhere when it comes to my family gatherings! And he ALWAYS wants to go as well. So am I wrong for being upset? It's seriously funny to me cause he wants all these ppl I've never met before to all come to MY baby shower that IM PLANNING WITH MY FAMILY, but yet I don't ever get invited to his family gatherings.