Oh god I've been there and I'm so sorry. It sounds like you need to go to a proper psychiatrist and get reevaluated. Just being on antidepressants won't help ****.
Also, I'm so sorry about your loss. Grieving on top of depression is a lot.
Big hugs to you. All I can say is that I've been through it and the only thing that helped me was time and reminding myself that these feelings, and all feelings, are temporary.