My wedding is very far off (August 2018) but I am already stressing about how to seat my parents and how they will interact. They were divorced when I was older (20) in an ugly affair situation after a previously happy marriage fell apart; with no young children, they had absolutely no reason to see each other, and haven't really seen each other for the past 6 years. Every time they do they both get upset. To further complicate things my mom is still dating the man she left my dad for. I don't think it's appropriate to ask her not to bring him, and my dad despises him even though he is very happy with his girlfriend (who I love and will also attend). I have literally no idea how to seat them in a way that isn't awkward and I don't want to tip toe around their awkwardness all day/night or task my sister with doing the same. Can my FH and I sit at a table with just the wedding party so I can separate my parents? How can I say politely that they need to get along for a day for my sake?