Sounds like a polite way of saying "Well, we may or may not come, but thanks for the invitation."
Who cares if they go to a reception for a couple of gay guys? They're adults.
I think it's actually a great opportunity to witness.... "If anybody has a reason why these two men should not be joined in holy matrimony, speak now or forever hold your peace."
Can you just imagine those gorgeous twins shooting their hands up to speak their "peace."