Post Partum Depression = weight gain, more depressed

Hello all, I haven't logged onto here in about 2years. Since my WLS, I lost close to 100lbs, I felt beautiful and healthy. One goal was to get pregnant, and I did. I did not gain 1lb with my pregnancy, After I had my baby, I fit into my clothes with ease. Then post partum depression hit me..... I was put on meds and I have gained 40lbs, I don't know what to do.. I self weened from the meds because even my maternity clothes fit me tight!!!! Nothing fits me and on to a size 16-18. I am not hungry all the time like I did with them, but was wondering, the pouch test thing, would that help me get my tummy back to the size, I am so confused, I feel like I did the WLS and failed. Any suggestions, should I start my post op diet phase? I have no idea where to begin. Someone help please