I'm part time and with a partner and still want to run away from the constant something to do or someone who needs me.
You sound burnt out and in need of some breathing room.
Do you have enough savings to request a week of unpaid leave? Child still in nursery but just take some time to decompress and regroup
I would defintely say work smarter not harder
We do not bathe our 2yr old daily (assuming she isnt filthy)
Get some good meals sorted for yourself from cook or mindful chef frozen range
Have online shopping for a wfh day
Get a robot hoover and set it off at night
Load of laundry each night hang up before bed through out in the garden on the airer next morning if sunny
Streamline and minimize little ones clothes and toys if it's all too much
Take half a day AL once a month to do life admin - sorting out MOT, bills, birthday cards etc
The time your ex has them do something for you - lunch with friends, swimming, manicure etc
Find a good reliable childminder nearby and set up a standing day once a month (my friends nursery staff did babysitting which was great)
If your working FT and your expartner seems them every weekend are you getting to do anything fun with them and enjoy them reguarly like swimming lessons, messy play etc?
If your nursery closes for a few weeks a year then you ex should be using some of his AL to cover that as well. Full payment of money is great but not when you have no actual time
It will get better stay strong x