Father (31 with a new baby) looking for advice. Ladies, please pitch in too and tell me if I'm being an ass.

My wife and I just had our second daughter; it was an emergency C-section as the baby's activity had greatly reduced, even at 35 weeks, which my wife noted and we went to the hospital for a scan. Our gyn informed us that it would be better to operate and remove the baby, which we did. The baby was born and is healthy, and I couldn't be any happier, except for one thing.

My wife seems to be miserable (same thing with the first pregnancy), and I don't know what I can do. She's complaining that she has no help and that she wants to go and stay with her mother (quite a distance away), whereby we wouldn't be able to stay together as a family for a period. Since I'm a work from home dad and we're currently staying with my mother (we rent our home out to increase our income), I make it a point to always check on her and the baby multiple times a day and ask what she needs. I help with the new baby whenever I can, I look after the first one (still under 2 years old) as well, and I work a consulting job. I don't turn down her requests, ever. If she asks me to do something, I do it no matter what I was up to before.

This morning, after the baby woke up, she got frustrated and upturned the baby's mattress and threw the blanket, as she said it was slanted. I told her not to get too frustrated, as it was only a small issue which could be easily fixed. We ended up having an exchange were she mentioned "You're not that good a husband," in a pretty hurtful way. It really stung because though I've not been a perfect husband, true, I'll be damned if I don't look after my wife and children. I told her that she can be really horrible some times, and that I felt taken for granted. I took a mattress to stay with her and take care of her in the hospital (even helping with sponge baths), I look after the firstborn, I completely quit drinking alcohol recently because it was hurting the marriage and me, I don't stay out late with the boys. My ma has also been super helpful with watching our firstborn, putting her to sleep, offering us a place rent free whilst we build some income from rent. We have a hardworking helper at the home as well. I also have the sole responsibilities for earning as my wife has been taking care of the first baby at home (which is a huge job in itself and I don't pretend its not).

I often work till late, run up and down the house multiple times a day, bathe and clean the first baby when she inevitably gets dirty or pees/poos on top of the many errands that have to be run. I'm literally trying to do my best as a young dad because I know what growing up without one feels like (my own passed away a month before I was born). I sometimes consider having a beer here and there, but I know what a slippery slope alcohol is and how much I used to love drinking. What can I do to help my wife with her blues/ppd/negativity? How can I improve my sanity?