So, here is the quick backstory: My cousin, his (now ex) wife and I went to college together and were close during that time. I was at their wedding years ago and used to babysit their son while he and his wife were in graduate school and I was finishing undergrad, which was about four years ago. In the past few years, he had an affair with a much younger woman, gotten divorced, moved away and he and I haven't spoken in more than two years. However, I do still stay in contact with his ex-wife and their elementary school-age son. Is it acceptable to invite them my wedding but not my cousin?