How can one live being completely dependent?

I recently returned from visiting my grandma, aunt and uncle in Escondido, CA. It was awesome to see my aunt and uncle who I haven't known well throughout my life. They are always saving dogs and now have 3 weimaraners (Tia, Remy, Brandy), a Rhodesian ridgeback (Casey), and on the weekend a chocolate lab (Mocha), along with a small schnauzer (Gus Gus). So they have a crazy house but love every one of those dogs. Mocha swims just like a person would and goes to the hot tub when she gets tired. Its great. I loved getting to know my family as more than just names. Then, I also saw my grandma who is living with my aunt and uncle. She is 100% dependent on others to help her. She has a nurse who works from 8-5 during the weekdays because she can't even walk to the bathroom which is 5 steps from her bed. Someone has to do everything for her and she is starting to get lazy instead of fighting to get better. After she fell off the steps of a plane, she has gone downhill falling multiple times after. I can have a conversation with her just fine but when other people try to talk, she gets overwhelmed and doesn't make sense. Its because of other people that she is alive today since she can't do anything by herself. Most of the time she can eat if her food is all cut up but if she is tired, she can't even do that. Seeing that made me wonder, what is the point of life? There is such a difference from living and being alive. Could I ever live my life in constant need of assistance or would I have the courage to just let myself die. I wonder if she is scared to die, or feels like she still has to do something on this planet. When she was younger, she swore she would never live with one of her children and obviously that is no longer the case, so when I get that old, will I change my mind? Will I let myself become just a breathing thing that really serves no point? I think I need to be happy and help others to consider my life worth while. As of now, I am not scared to die. I would of course rather live because I love the time I have, but if I were brain dead, or unable to function for myself, I just don't see the point. It makes life drawn out and not so exciting. We have so little time here on Earth before we are whisped away so why not make the most of it. As the saying goes, "life is not measured by the number of breaths you take, but by the number of moments that take your breath away".