Upset!

Am I that bad? Well my grandfather and grandmother sent me an informal Wedding Shower Invitations through my half sister for their 60th wedding anniversary with a message that they want me to pay for their giveaways for their wedding. I was upset because first they did not invite me personally. And they only contact me if they want something. Hello!!! So what I did, I ignored all their messages and just few days ago I saw all their happy faces pictures online. All present (dad's side) including my stepmother and her kids except me. Whatever!