You sound like you hate him.
I can understand a lack of sympathy with a hammered adult whose illness is entirely self-inflicted. However, you knew he wasn't drunk and was just ill.
If I was living with a friend who that poorly, let alone a partner, and I'd heard them be that sick in the night, I'd have got up to find them something to throw up into as well. Instead, you quietly seethed, probably predicted the vomit but set your DP up to fail by refusing to help him until he'd caused The Big Stink.
I'm generally very good at not causing any mess when I'm sick, but once I woke up with a sudden uncontrollable desire to vomit, and the plastic bag I frantically grabbed in the dark had a hole in it. Sometime these things come on with very little warning, which is the point - generally the body realises there's something bad inside and it needs to get it out before it makes you feel any worse. It's inconvenient when we're sick, but it's rarely intentional.
Given you used to have warm, fuzzy feelings for this man two to three months ago, and you've been diagnosed with PND before, what's the harm in having a chat with your GP about disconnected you feel from your positive emotions? Maybe it's not PND, but wouldn't it be good to have a doctor tell you that, so you can feel more sure about your decision to leave?
Or maybe it is PND, in which case, maybe you can feel love towards your DP again, and you haven't to go to all the hassle of moving out with your kids. That would also be a good outcome.
Whatever the the answer, I think talking to the doctor can only have a good outcome for you. Please do seriously consider it.