I realise that it isn't even the same level, but the emotional disconnect with making plans makes sense to me. I still have resistance to the idea of planning around Christmas - the connection of the event & Dad is still very strong. You did things with your lady - she was the glue that made making plans make sense. She's no longer there, there's a hind-brain response saying "don't do it".

I could be wildly off, but it makes sense to me.