Grief 24 Weeks

Long story -but my beautiful young healthy mom was told she had a rare cancer and its terminal (inoperable and uncureble)- extremely shocking. I'm trying to stay strong for my baby and my mom but she's my favorite person in the world (as well as my soon to be son). Has anyone had similar experiences during pregnancy? I wake up crying every morning and so sad. I just hope I'm not hurting the baby.