Hardships of the 4th Trimester

Why is the 4th trimester rarely talked about? Nobody had any length of discussion with me regarding what it would be like after my child was earth-side. I was as prepared as I could be for pregnancy and birth, but the months after birth is what shocked me most of all. Undoubtedly, my 4th trimester was my hardest. Maybe it was because I had a long labor.  51 hrs with a hospital transfer and a few hours of pushing. The painful months of not being able to sit comfortably, breastfeeding challenges, and the lack of support I felt were main contributors to recovery, no doubt. I wish now that someone had spoken to me about postpartum depression and the many ways it manifests itself.