Oh Cupcake, poor you! I've been wondering how things have been going (I posted on your earlier thread).
You said breastfeeding isn't working this time- well, it is, your DD is alive and gaining weight, being nourished by your milk. It IS working!
She may have a medical issue that is causing her discomfort and needs to suck a lot to make herself feel better. Or the tongue tie might have regrown- a medical issue that can be fixed. You've arranged appointments, so for now that's all you can do in that department.
You breastfeeding isn't the thing causing the problem, that's a daft thing for your DH to think. And not particularly helpful of him either. The problem is a separate issue. Might it help to have a talk with him on those lines?
I don't want to demonise your DH because having a newborn is tough for everyone in the family. Maybe he's forgotten how tough having a newborn is? Or maybe he's worried about you getting pnd again and wants to try to make things more controllable ( along the lines of "bottle fed babies only feed every 4hrs, my mum told me so, if only DW would bottle feed, DD would conform to my mother's 1970s ideas about infant feeding"- nonsense of course, and totally ignores the fact that there's a reason why your DD is feeding like this, probably a medical reason. But if that is his thought process it should be easier to make him see sense than just having a row about it.
One suggestion for today: can DH put her in the sling and take her out for a walk so you can have a break / some time with your other one? I get that she will probably protest, but you need a break and she will survive for an hour with her dad.
Hang in there, you are doing a difficult job very well!