Im so sorry for your loss. I do understand. Ive lost 3. Motivation and all that goes along with it goes out the window. Its a struggle. All the questions you ask yourself. Is it my fault, was something wrong with the baby, is my diet adequate, did i exercise too much, was i too stressed out? Honestly, after some soul searching, I learned that it wasn't my fault at all, and those babies were in my life at the right time, and I didnt do anything wrong at all. They taught me how to love someone so much more that i could ever love myself.
Your motivation will come back, but you have to make peace with yourself before you can move on. I wish you the best.