I wouldn't call where my last house was as isolated. Just a street on a huge hill (which thieves ignore), with houses on 2 acre lots of woods. I could see the houses of both my neighbors, but I was not close. The house before was in a typical cul de sac newer home neighborhood. The lots were also 1.5 to 2 acres, but mostly lawn and not as big as my last house. It was in a more rural suburb than Concord, but neither of these places qualify as isolated or "country" to me. I don't worry about intruders, etc., maybe because the crime rate is low here. Some think it's weird, because there's a medium security prison in my town, but, it's like part of the fabric of life here, it's on the highway, and has been here since the 1800s. There's also a minimum security prison, here, a farm, where prisoners are trained in various trades. This is right behind the hill and conservation trails of my former neighborhood. We could hear the softball games in the prison yard in the summer. Only once do I remember someone breaking out, and they did not run up the hill to escape... so, what Shooting Star mentions is not even in my thoughts in thinking about where I will live as I age. I certainly don't want to live someplace really rural, as we enjoy the amenities of small town life, with being able to walk to restaurants, shops, etc.
But the prices that Pax mentions, well, the last time I saw that was when we sold our house in Tempe, AZ, in 1990. I don't think there is anywhere in MA where you can buy for 95K.