Thanks Sandi that makes a lot of sense to me now.
I do have a dilemma now though.
I have agreed ( based on how well yesterday went)to maybe doing something on one of the Easter days together.
Nothing is set in stone and no arrangments made but it has been agreed in principle.
So how do I cancel that without looking like some indecisive fool.
I had considered saying the following and would appreciate your thoughts.

'We had a really good day with the boys yesterday and it was good to be able to spend time in your company without getting into a conversation about us. But I don't think it really helped either of us, considering that you are determined our marriage is over. All it did was remind me of what I am losing and I need to try to move on with my life. Also I think it sends mixed messages to the boys as it makes them think that perhaps we might be getting back together.So I don't think spending time together over Easter is a good idea, you can spend time with the boys on your own and I will do the same. I'm sure you understand where I'm coming from'

How does that sound, is it even necessary to explain myself?
I just don't want to come across as being weak etc so give me your thoughts