As the saying goes, no one knows how to push your buttons better than your family. When you're raised together or spend lots of time together, you soon realize just what makes people tick. In this family , there's a silent war going on between the OP and her half-sister, who always tries to one-up her at everything — even her own engagement party. The OP shared this infuriating tale to r/pettyrevenge, but in my humble opinion, this is pro-level revenge . After announcing a party to celebrate he…