I have no advice but want to offer a handhold.
Can you put pause on your PHD, even for a week or so to sort things out?
Are you working? If so, take a week off sick?
You need some life admin time. Time to be alone, clean your space, clear your head
How old is your dd? Is your husband good with her? Can he take the reins for a week?
I'm so sorry about your mum. How long does she have left?
Honestly girl, breakdowns happen to us all, ive been there and I think thats what's happening here.
Can you contact the gp tomorrow morning as the first port of call?
Then figure out an apology speech for your friends?
Your husband, I dont know, is this the only thing that's wrong?
You need a week to spend time compartmentslising. Writing down each problem and being clear on what they are, so you can decide on how to go ahead.
But if nothing else, I love mumsnet as it is just the best support. No judgement from me, ive done worse when I've been very very down. ❤️❤️