Do you ever wonder if you get ill

I mean chronic or terminally. My dad is now terminal and it's all a blur. Happened within weeks. I sometimes think of I make it to my 70s or 80s and get ill, I'll have no one to be with me. I'm very grateful to be by his side, talking, holding his hand and giving any love possible. If I wasn't here, sometimes nurses don't come in for hours.
Bec I have extreme anxiety with dating, question my worth, I may not have a partner to help me one day, and most likely no kids. It makes me sad, and scared no one would advocate for me...but I try not to think about it.