There is a dark side to the idea of an 'internal locus of control.' It creates a sense that the individual can and should manage the situation, even when the situation is totally unmanageable. I think it's a common problem among high achievers (particularly entrepreneurs), and conversely some 'resilient' people need to accept that there sometimes really IS an external locus of control before their efforts to control the situation break them.
Hence the serenity prayer (https://en.m.wikipedia.org/wiki/Serenity_Prayer) and major parts of eastern spiritual traditions...