It is precisely my point that these 'external' sources of change are nowadays one of the main problems and entirely foreseeable in advance. For example, if one

It is precisely my point that these 'external' sources of change are nowadays one of the main problems and entirely foreseeable in advance. For example, if one or both of them prioritize their careers over their marriage, and spend no more than an hour or two a day even in the other's presence, let alone quality time, for years on end, because they're busy at work or with something else...it's entirely predictable that they grow apart. That was the failure. They chose economics or the corporate ladder or an app that's changing the world or...over their marriage.