The time it takes for a person to get over postpartum depression depends on the severity of the postpartum depression.
Some people get over the postpartum depression sooner than others.
Postpartum depression can go away within 6 months of giving birth and other times the postpartum depression goes away after a year or so.
I was so depressed and thought that I made a mistake after giving birth to my first child who is a boy and it was very stressful and at least for the first month I wasn't feeling much love for him.
I felt like it was a chore to take care of him and thought about adopting him off but after 6 months I started loving him more and wondered how I could even think about giving him up.
Then a year in he was getting more and more enjoyable and the depression fully went away for me after he turned 13 months old.
I didn't experience the postpartum depression after the second child but did with the first.