I seriously need some help.. my baby girl is already 3 weeks old and my postpartum depression has…

I seriously need some help.. my baby girl is already 3 weeks old and my postpartum depression has only seemed to become worse. I love her, she is so beautiful and perfect. But I don't feel like her mom or that I have any purpose being around. I don't want to be on medication but how long will this last.. :'(