"My heart is breaking, but I just have to keep shutting it off for right now. It is just not safe to grieve."
I'm not certain what you mean by this, but as devastating as the grief reaction can be, it is most assuredly safe to grieve. You can work and grieve, and be a student and grieve, and be a parent and grieve. It is not safe to not grieve, and it is unwise to keep shutting it off. Grief takes a long time and it becomes integrated with the routine of life. Your grief will touch everything. You can't avoid it so make a friend of it. You will remain functional and you will adapt, adjust and move on exactly when you're supposed to.