I'm over seventy, and I can just say I can't do it because of a medical condition. I actually liked being on a jury. It's easy work, and I think people who are reasonably intelligent should be the ones on juries. At night, I sleep for one to two hours at a stretch. Often I spend two to four hours reading in the middle of the night because I can't get back to sleep. For this reason, I avoid anything that involved being somewhere early in the morning. If I have a bad night, I shouldn't be driving, and getting to the court on public transportation is tricky. I'd probably take Uber if I had to show up. $$$ The last time I had to show up, I slept through voire dire.
I called the court, and the clerk told me to write a letter or an email saying that I was over 70 and couldn't serve because of a medical condition. I tried the email, and their website wouldn't allow me to be excused. I wrote a letter and sent it snail mail. A second clerk told me the same thing. I'll wait and see what happens. The clerks said I'd get confirmation. Since the website wouldn't let me get excused, I wonder. And I don't expect a snail mail response anytime soon. Will you visit me in jail? I'll probably have to show up some time and tell them in person that I can't serve.

I'm sorry about the death of your friends. It's hard losing people you care about. I'll say a prayer for them and for you.

Good wishes.