So sorry you are hurting. You do have a lot of pain & loss to bear and good reasons for being depressed. It's normal given the terrible losses you & your kids have suffered, even though it does hurt so much. Please hang on for your kids. They need & love you just like you need & love them.

I can only suggest seeing your doctor again, adjusting the medication again to find the right one.
But also, maybe someone to talk to, a pastor, priest, counselor perhaps? Gentle Hugs to you ~