The sadness and sense of loss, along with the symptoms makes the disease overwhelming, but like others have said, you will find a new sense of normal, and things will get better. What made it better for me eventually was realizing that although I had all of my symptoms and had to take all of the medicines, I was much better off than many others.
Maybe your doctors should prescribe an antidepressant? Depression is very common in MS from either the effects of the disease, or just for dealing with all of the symptoms and the sense of loss. I have been on AD's since my diagnosis.
God bless you!