Inoue- I have had similar feelings in the past. And I can assure you that your family does care. If not your family, someone that is important to you. I think the depression just takes hold and you can't see things as they truly are, and you don't see people as the loving caring people they are. It is the nature of depression.
Years ago I remember having Christmas with my extended family it was a terrible time for me. I remember going home and laying in bed crying about it. It was so painful my stomach hurt and I was thinking "why don't they love me, what have I done". Several months after that my grandmother called me to try and get me to see a counselor. She mentioned Christmas and said taht was when everyone got so worried about me. I seemed so distant that day and they didn't know how to get me to realize how much they love me. That conversation was very telling and I went shortly thereafter to a counselor. It has been much better ever sense. I have not had those feelings again.