As I said above, there may be a BF solution to her problem (eg deal with tongue tie, get latch sorted, heal nipples), at which point BF may well be the easier option for her long term.
Except it's been 4 months already with no solution in sight. I think if there was going to be a feasible solution it would have already come. I can't imagine there was a solution to heal her nipples that she just decided to ignore. Her baby is almost old enough to start solids and weening.
I really don't think OP's husband values BF if the tongue snip is HER Christmas gift when it's THEIR baby. Why is it not also his gift if it's equally as important to him as well?
I think her DH is supporting whatever decision she's making, and trying to keep her above water. Otherwise he would not have gotten up and actually cleaned the jug when she woke him up.
It's not a matter of breastfeeding or formula feeding.
If a mother was talking about constantly getting blisters on her feet and sore joints from walking her children to school when she could easily put them on the bus, everyone would encourage her to put the kids on the bus.
Most people are supporting the OP, in fact there have only been 1 or 2 nasty unsupportive comments. It's a matter of this situation is not sustainable, she's given it an honest go for 4 months (which is nothing to sneeze at), her nipples are not healing, she's miserable, and it's affecting her family life. It's time to look at alternatives.
If nothing else, it will be easier to access AD's she may need to help with PND, some AD's you can't take while breast feeding. Her PND really needs to her priority, her baby will be ok on formula, she needs to take care of herself so she can in turn take care of the baby.