I would hope you could talk to your sister and husband but we are not always able to talk about these matters even with those closest to us. Some people are just not capable of understanding.

If your doc put you on Zoloft right after you had your daughter I am assuming it was due to post pardem depression. That can really be difficult when you are supposed to be full of joy....and then your aunt. Grieving is a process and bounces around between a number of stages until you get to acceptance. Some people get stuck in depression and need help getting past it. There is a section on post pardem depression and one one grief I believe.

I would make that appointment. You may need to up your dose or try another med. Your mental health need only be between you and your doctor and whoever else you choose to tell. Maybe you don't tell anyone but your doctor. I think we need more support than that but it has to be the right people. These forums are a good place to get support without being judged. What you are experiencing is real and valid and we understand.