We've been separated for almost three years now. He was always fairly useless when it came to the DC and has stepped up considerably since we left. However, he still falls way short of the mark and quite frankly, I'm sick of picking up the slack and the vast majority of the responsibility towards the dc falls to me.
This is exactly the case when it comes to their birthday parties. I have to do all the arrangements and usually pay for the whole thing too (he always agrees to pay half but has only done this twice and not paid the full half on a third ocassion. He still owes me £100's for his half of parties and presents for the last few years). He always invites his family and their dc even though some of them are too old for a very young child's party. What irritates me the most though is that he will invite my exSIL (his brother's wife) whom I absolutely detest. She has been absolutely vile to me in the past and I resent the fact that I can't enjoy my DC's parties (that I organise and pay for usually) because having her there glaring and judging me puts me on edge. It's not necessary for her to be there as her husband comes as well and afaiks she sits there chatting and not actually looking after her very young children. Despite this, my XH absolutely refuses to allow my new partner and his son to come to the parties even though these two people are important and involved in our DC's lives. He doesn't have a valid reason for this, it's just because he hates my DP despite having never met him (XH refuses).
The last party was the final straw. XH did precisely zero to help out and sat at the back drinking with his family at 10.30am. I was so flustered trying to do everything like get the food out etc. even the entertainer and other parents offered to help me. It just feels like a slap in the face to have him enjoying this time with our DCs when he puts in no effort whatsoever. I personally think it's so he can show himself off as a great dad. He often invites his friends with children that my dc don't see or play with. It's all for their benefit I believe. He also still owes me money from this party too. In contrast, my DP stayed up with me making sandwiches the evening before and ran to Tesco at past midnight to pick up more icing for the cake. All this for a party he can't come to.
I would rather have DP there supporting me and helping at future parties so WIBU to just do my own thing and not tell XH about the arrangements so he can't come or invite his horrible family?