How long will I feel so sad?

On March 10, 2015 the test said pregnant 2-3weeks. On March 26 I went to the hospital because I was bleeding. They ran blood tests and told me I was having a miscarriage.  The hormones lingered around until May 8th.  I still cry when I think of my little baby. We named her Camryn (we saw something that said all human life begins as female so we decided it was a girl). My sister and my cousin are both pregnant and die after what my due date was with healthy babies. I see them and hear their updates and I just want to die. How long does this sadness last? I want to be happy.