Being alone isn't always a bad thing. In Moon Over Manifest, it's actually good that Abilene has some time away from her dad to do some growing up, and Jinx sure as heck needed to get away from Finn, right? The people of Manifest seem to be content in their isolation, too, keeping to themselves in order to avoid feeling any more pain. But as far as we can tell, isolation causes more bad than good in this book. It's definitely okay to be on your own, but you always need someone—or many someones—to have your back.
Being isolated can totally corrupt a person—think about Finn.
Isolation can bring out the best in a person—think about Shady.