third trimester depression?

I am 37 weeks pregnant. With my third child. I have spent many hours in the past month locked in the bathroom crying. I feel like I'm not a good enough mom. I'm not a good enough wife. My family deserves better then what I am giving them at this point. It's like nothing I do is right. 

My house is messy. Laundry is undone. Dishes are unwashed. It sickens me. But I'm so tired. My back hurts. 

Everyday I look down at my belly and I resent it. I should be glowing. I should be grateful to be pregnant. Some women can't get pregnant. Instead I'm very unhappy. 

After I had my Second child (18 months ago). I was experiencing PPD(post partum depression) pretty bad. I had to stop seeing my therapist because of financial reasons and I tried zoloft for a few months, it didn't work out. I am starting to wonder if its still the PPD. Or maybe I am just insane.

I can't remember the last time I hung out with a friend. I feel so alone and hopeless at times. Husband works so hard, he shouldn't have to take care of me too.