Sharon, Sorry for your ordeal, and I hope Bruce didn't suffer in his death. I agree wholeheartedly about telling your friends and family that you love them and they will be missed. Even if one of you dies days or weeks after the last contact with them, the message will be there.
Part of the bargain of living alone --especially if you have no landlord and no employer--is that if you die unexpectedly, it can be weeks before anyone finds out, even if you are not a hermit. I, for instance, occasionally go several weeks between phone calls to individual friends or family members, and they don't keep each other posted on when they last talked to me. I am often out of town when my car is still in front of my house, so seeing the car but not me does not trigger an automatic alarm for my neighbors. If I started pulling no-shows for my business appointments (music therapy and entertainment), I'd have a lot of folks mad at me, but I doubt that any of them would call the police or in any other way try to investigate. (My regulars might, and they would no doubt leave messages on my voice mail, but I doubt they'd call the police for a few days or weeks. And remember, if you're the homeowner, a search warrant would be required to enter the house.) Sometimes I do not have a tenant sharing the house. If it were winter, it might be a long time before neighbors noticed the smell if I died, and they might just think it was a dead possum under the porch or something. (That happens occasionally.) The first clue would no doubt be the mail piling up in my mailbox--provided that mail thieves didn't help themselves every few nights.
The point is that even if there are a lot of people who notice your absence for days or weeks, unless you have an employer, family or close friends with whom you check in regularly and frequently, it could be a long time before anyone would take the steps necessary to discover your death. (CapriUni, your situation is a case in point.) Friends and neighbors may assume you're out of town or maybe just under the weather or working overtime or just staying indoors for whatever reason.
What worse is, you could die slowly and unnecessarily because you were incapacitated inside your home and could not get to a phone. I think that's a side effect of our living very mobile lives in big towns where neighbors don't know each other's business.
Mudlark, I think your idea about having a network of folks to check in with regularly is a good one--especially if you have animals. But it can be a pain in the neck, too. Personally, I hate the hassle of HAVING to contact any one person every day or two (unless I'm seeing that person every day).
Capri, thanks for the info on hormones and heart attacks, too.