iklien, I'm so sorry this is happening. It sounds like they need to realize how much their bickering is stressing you out, and they need to be reminded what the day is all about. Not many guests are going to care what brand of vodka or congac is
on the table.
I would seriously threaten to cancel the whole thing unless they all grow up and start acting like grown-ups. They refuse to be in the same room together??? And these are adults? Oi! I have very little tolerance for senseless bickering and
bullshit, so I'll be SO willing to walk out if my family started acting like this. I'd start chastizing them like little kids. This would be me ---> "Your behavior has been embarassing and there's no way I'm walking down the aisle
with this animocity and tension. You all need to get along or there won't be a wedding."
Take a deep breath... maybe two. And give yourself a moment to decide how much of this you're willing to deal with. There's only so much one bride can take!
As far as the seating chart goes, perhaps you and your FI should do it without any input from the parents. And tell them to just deal with it
Oh, and that massage sounds like a great idea too. Hang in there, just 2 more weeks. We're here fo you.