PTSD and PPD

I really need advice. Whenever I was younger I was sexually assaulted and also physically abused by a ex boyfriend. My PTSD went away almost completely whenever I was pregnant however now it’s back full force with the nightmares.

I seem to also have postpartum depression as well. I recently started getting extra stressed because I haven’t been sleeping good at all with our baby and then the nightmares. I started taking it out on my fiancé and I’ve been really snapping at him. I’m not sure how to really handle this.

I don’t want to go to therapy. Should I mention both to my obgyn at my check up? Do you think they will prescribe medicine?