Dear Prudence,
Five years ago, I married the love of my life. We did not invite my older sister, from whom I was estranged at the time. My older sister has a history of making public scenes and has repeatedly refused psychiatric help, despite the many entreaties of our family. The wedding was attended by both of our families and we had a lovely time. This year, my sister is getting married. In spite of the fact that we have resumed a relationship (of sorts), I am not invited to the wedding. I am hurt, and want to ask my parents not to attend. How do I deal with this, and can I ask my family not to go to her wedding?