(warning: long post)Fed up, confused, and alone

I'm writing this hoping somehow I'm not alone, but in a way hoping no one else is going through this. My husband and I were friends for 1 year before we started dating, together 7 years before engaged, and married almost 3 years in October. I'm 31 he's 36 and we have an 8 month old beautiful baby girl. He was excited when we found out I was pregnant, he promised to be helpful and supportive(neither of which he kept). I was diagnosed with gestational diabetes and placed on a special diet which I have continued since giving birth. I had some complications which resulted in our little girl being born 7 weeks early and myself being placed in the icu for 2 weeks. After being discharged from the hospital I had lost all the baby weight and then some for a total of 50 lbs lost. I'm continuing to lose weight thanks to the keto diet. However my husband recently told me that he's not as attracted to me as before. He showed me a picture of us when we first started dating and said he'd like me to look like that again. I'm taking this badly as I also have post partum depression. He's picking fights and arguing over petty things. We are currently sleeping in separate beds on different floors. He says he doesn't want a divorce, and neither do I because I love him. I don't sleep anymore, and I don't feel like eating. I'm embarrassed to talk to a doctor, because I feel like I'd just be whining. Sorry for the long post, I just needed it out.