My cousin ghosted me — should I go to his daughter’s wedding?

Dear Eric: Three years ago, I had a falling out with my cousin, Harris, at a family gathering. Harris, like me, is a retiree in his mid-60s. We have been friendly before this. Harris also has three siblings, and I am on great terms with all of them.

He confronted me about something I wrote in the family gathering’s logbook that he found negative. I attempted to apologize, but he rejected it and refused to talk. He left the next day, and I have not seen him since, nor had any contact as of three years later. I wrote an email a month after the incident, saying I wanted to talk; no reply. I wrote a letter four months later and another letter a year later, in which I implored him to call or email. Nada. I phoned, left a voicemail at one point, also not acknowledged.