my sister is pregnant

Kaycee
So I've had a really rough year this year. My husband and I have wanted a baby very badly. The Lord blessed us with a beautiful son whom we named Jeremiah, however our sweet boy was stillborn. 6 pounds of absolutely handsome… He was born on June 26 and we had his funeral on July 2 this summer. It was really hard to watch such a little casket be lowered into the ground, and since then we have tried to get pregnant again and it seems almost impossible. 
As my friends and family have announced other pregnancies along the way it has become really difficult to be excited for them even though I really want to be...
Last night I found out that my sister is expecting another baby, and she really didn't want to be pregnant again yet. Of course she is excited regardless and would love the baby anyways, but she just really wasn't ready to be pregnant again as her baby is only five months old. 
i'm very happy for her, at least as much as I can be … But my family had to tell me that her due date is the same as my sweet Jeremiah's was... i'm really struggling with this news and will take any advice.
… I am so tired of getting negative test results. I'm crying even as I try to write this post