Splitting with a partner and custody of newborn nearly 6 months

I’ve just recently had my ex end things suddenly and not in the best ways where an adult conversation takes place. I have always been the primary carer since day 1 and only spent 2 days away from baby due to being in hospital and have pushed her development with baby classes and always been the decision maker around feeding and now weaning and also paid out money when he hasnt at any stage up until now. As my lo is such a routine driven baby I initially depsite how he conducted himself was going to allow 2 set block nights each week but my lo has severe seperation anxiety and when i explained to her dad that it needed to be 1 overnight he said i was over reacting and in a previous conversation that hed pay when he was on her time despite me saying we were both equally responsible for her needs regardless of days

Has anyone had any issues around this type of situation and how to manage without getting into a bitter situation 🙁