I know the general etiquette is that you never split up couples, but I wanted to get everyone's input here, because I'm conflicted. (As an aside I'm not sending out invites or STDs yet, but I've been wondering what I'm going to do about this ever since I got engaged)
My grandparents went through a very nasty divorce many years ago. Essentially what happened is my grandfather carried on a very long and public affair that was known about by basically everyone besides my grandmother. Eventually my father (who was about 22 at the time) found out about the affair and told his mother the truth after my grandfather refused to come clean about it.
What happened over the next few years was my grandfather would promise to stop seeing this woman then my grandmother would move her entire family to a different town to get away from his mistress and the woman would follow them. Apparently this happened three times. Eventually my grandfather left my grandmother to marry his mistress, leaving her to raise their younger kids alone.
My grandmother never remarried or dated anyone because she is extremely Catholic and doesn't believe in divorce. My grandfather knew this when he left her.
The way things work in my family is we don't acknowledge this woman's existence. My grandfather doesn't talk about her when he visits us. I have only met her twice in my entire life, once when I was really little and once when I was around 16. Neither of my cousins who are married invited her to their weddings. My grandmother still has a really hard time being in the same room as my grandfather (he has done things over the years to further exacerbate the situation) I don't think she could handle seeing the woman who he left her for.
Part of me wants to do the right thing in terms of etiquette and invite her, but part of me also knows the sort of massive shiit show that it would create on the off chance that she actually accepted the invitation.
What do you guys think?