I'm so sorry for your loss! One thing that should never happen is that a mom should never lose her child. It's just wrong! Have you looked in to a support group? I found MISS Foundation (Mothers in Sympathy and Support) to be invaluable, since the members experienced pregnancy and infant loss. It's difficult for many to understand the depth of that pain, versus the pain of losing an older child or adult loved ones.
I know it's easier to delve in to food for comfort and stay in bed all day. BTDT. My goodness, allow yourself that chance to grieve and wallow in self pity. You just lost your child! But do keep your own health or physical goals in mind. As another poster said, eating may offer you temporary comfort, but it's not going to heal the hurt. It may amplify what you are going through by building fat.
I lost my son after his birth. I had the baby weight and no baby. It was awful! Not just losing a child. You understand that part. But losing the child and still having the postpartum body. On a vanity level, that only added to the pain and the horribleness of it. It was like insult to injury. Part of my healing was getting back in to shape, losing the weight and getting ready to try again for another child. It was really hard to put myself out there. Everyone knew I lost my child. Sometimes it was torturous because it was like a big elephant was in the room and no one wanted to acknowledge it. But other times, it was a relief to escape my grief for awhile and put myself out there, and focus on something positive.
Exercise helps by giving you those feel good hormones, the same hormones that comfort eating provides without the calories. Being around people can help provide balance. Use your support groups or your therapist, and allow yourself to grieve, and keep putting yourself out there. You cant' go under, over or around the pain. The only way is through.