I think of those things that you describe as just existing, especially if they're just done on auto pilot without any feeling or desire to be here. When I think of being alive, I think of actually having a real life and being happy and so forth, like I was with my husband. Then, I was alive. Not that I wasn't suffering then too, but the difference is, I didn't mind the suffering as much because he was there with me and he gave me a reason to keep going. Now my reason to keep going is gone so I'm just existing, just going through the motions, but not really wanting to be here or enjoying anything anymore.
But I know each person sees it differently and feels it differently.