Try to fall back into God's arms and know in your moment of prayer that you are deeply loved for who you are right now. Also, talk to your physician about the depression. Depression is a disease that can be treated effectively with medication and therapy, but only a doctor can advise you on which antidepressants are safe during pregnancy or while nursing. In addition, here is a way that you can use your mind more helpfully. Facing and acknowledging the situation we are in always brings some measure of relief.
Denial splits the mind and makes it a battlefield.
You might begin by sitting quietly and writing out a full and honest description of everything that is going on in your life and body, including all your thoughts and feelings about this pregnancy. You especially want to identify the specific thoughts behind your fear about what might happen after this baby is born. Look at these fears as an opportunity to prepare for the fact that you may continue to be depressed after this baby is born. Once you make the decision to stop fighting your emotions and thoughts, you open yourself not only to practical solutions but also to the fact that God loves you now, depression and all. Very often when we are depressed, we feel abandoned and alone.