Postpartum depression is a bitch..

I have 2 beautiful daughter's, one who is almost 2 1/2, and one who is 2 1/2 months. I got the baby blues with my first, so when I had them with my second, it took me a while to admit that...when it was going on a little too long, it was something more. I did the proactive thing and reached out to a trusted doctor, got put on medicine. At first it helped. Then all of a sudden things got very dark, I love my girls, I love my husband, there is nothing situationaly in my life causing me to feel this way, but at times I'm not sure how I'm going to care for myself or my kids. I feel like I'm smothering, like I just want to go to sleep for a year. I'm not suicidal,I would never harm myself, yet these really dark thoughts about not being able to go on just cloud my mind. I'm lucky, my hubby is staying with our baby while I sleep next to our toddler because it calms me to be with her. But he has almost lost his job caring for us and I I feel like a troll of a mother and wife, my house is wrecked, my relationships feel wrecked. I'm starting a new medication tomorrow, and I really hope it helps. It will help. This thing called postpartum depression has rocked my world. And I wish people understood more, or even I understood more. I love my life with my girls so much, yet I'm drowning.I just want to be the mommy they deserve.