Yes, there will always be death. That hardly strikes me as a reason to not combat it. There will always be the poor and the disadvantaged, too.
The majority of the problems you're describing exist regardless of whether or not we try to save people's lives.
Your behaviour doesn't match your words. As I said, as soon as you spend one cent or one second improving your mom's life, you're spending resources that could be devoted to fixing the ills you're talking about.
The alternative is probably more true, that you think it's okay spending some resources helping your mom as long as you balance it with spending other resources fixing the ills you describe. You could even put a dollar value on it. Sum the dollars you spend to see her, or to hang out with her, or gifts, or whatevs. Sum the time as well, chatting on the phone. Agitating to protect Medicare, etc. And then you can compare it to the time and money you spend dealing with the other fundamental ills. Then you can see the ratio as to how much you actually care about either.
I'm also spending resources on my mom. I just do it in ways that could help your mom too. I am also working on the other ills you describe.
People also seem to worry about overpopulation. Now, I guess people use 'death' as a mechanism to slow overpopulation. But as long as births outnumber deaths, you've got that problem happening regardless. 350k people born each year. 125k die from aging or childhood poverty. Strikes me that 'wishing people die' to 'solve' the overpopulation problem is probably looking at the wrong part of the equation.
The problems you describe whether or not we battle aging. "A decade of decrepitude then death" shouldn't be in our solution set.