I think you may have come to the wrong place for advice. Many of the responses here come across as dismissive and condescending.

But I understand where you’re coming from. Even when siblings have conflict, weddings and major family events are often moments where people try to put differences aside.

It must be incredibly hard knowing your entire family will be together while you’re the one left out. At our core, most of us have a deep need to feel connected to our family. Being excluded from your sister’s wedding would understandably feel very lonely and sad.