work an intensive job full time (upwards of 55 hours a week, mainly working from home) so has she spent 11 months tiptoeing around whilst you David Brent loudly on Zoom?
Handling any small wakings between 8pm-midnight good you've got back onto this. Do not make a massive deal out of it. She's getting less sleep than you.
Cooks and feeds breakfasts nearly every day does this mean she gets a lie in or os she doing something else during this time?
Makes up bottles of milk at nighttime how much milk is she having overnight at 1?
Lots of, if not nearly all, housework - hoovering, cleaning, washing up, cleaning cat litter
All bathtimes daily
All garden work and house maintenance
You'll see this as you doing SO MUCH MORE THAN OTHER MEN but please understand, she's exhausted, touched out, sleep deprived in the kind of long term state whereby even if she gets a single full night's sleep it actually makes it worse!
You need to start helping with the night sleeps. If it's a night she's not at work the next day, then it's reasonable she does them, but when you're both in the next day, you need to split them. I'd start now by offering to take one weekend night. And don't just say that then leave her to cry because of you're sleep training covertly. If you want to sleep train, talk to her.
The housework should even put over time to her doing more as she gets more sleep and you do more nights
Can you offer her a night away before she goes back to work?