@chickendinnertonight I don't think your a bad person at all, I hope my message didn't come across like that. I totally get your ex sounds like a absolute arse, and most likely continue to be one 😔
I just think on this situation if you can spare any grace, give it to new partner and baby rather than thinking your letting ex off the hook again. She too may have thoughts on his behaviour and they may not be positive to be frank.
Any other occasion, set him alight and beat him with a stick for this behaviour re contact. I wouldn't see many people being ok with it.
Speaking as someone who was in your DC shoes as a child my mum always told the truth re dad. In child like terms but she always let me know it wasn't my fault but she didn't hide the fact he was also a bell🔔 when it came to contact. This helped me process the things that were happening and I'm sure there were tears on occasion but at least I knew I couldn't rely on him so in the end I didn't end up waiting for him to show up like a puppy and that made life easier in long term.
I would say to him ok well I'm going to have to rebook this course due to needing to have DC, could you help with the costs ? Or ask him for financial help so you can get childcare/ summer camp for that week give you a breather. It does have to be give and take.
I haven't meant to jijack this post. I haven't actually shared the details of it before on MN, I just wanted to share from a mums perspective on the other side, just how badly this can go and to put it lightly - I don't think I have slept well since my daughter passing. I wish I had fought more for her so she could have had one last cuddle with my ex.
You don't want the regrets I have, re if this goes wrong and statically I was unlucky granted but I think some of mine will haunt me until I die. You don't want that, and I wouldn't wish it on anyone, even someone I truly hated.