In a nutshell - they have been divorced for 32 years and there is no relationship at all between them, even for the sake of their dc.
Our dd will be one soon and already DP and I are arguing about it. I feel she should be able to have her party, everyone should be invited and they should behave like grown-ups. DD may not remember this birthday, but it sets a precedent for years to come and I feel quite strongly that she shouldn't have to be stuck in the middle of this, and should be able to have a relationship with both of them without feeling as though she has to choose between them.
DP has very obviously been made to feel like this his whole life.
Would I be naive/unreasonable to think that DD doesn't have to absorb their age old feud and that we shouldn't be pussy-footing around it either?