I actually do not remember where I heard this, but I was unhappy at one of my past workplaces, and I felt like nothing made sense anymore. The purpose of my job, the product, the people... I would ask why or seek deeper understanding and received nothing back.
The advice was "when no one has your back, it's time to move your back".
It stuck with me because it applies to friends, family, work, and life in general. If you do not feel supported and able to give support back mutually then it's time to place yourself in a situation more beneficial for you and those around you.
It doesn't place blame, it's simply a validation statement - you feel x, so do y.
Love this idea. It's an idea that's easy to break down to children as well, help them narrow down their options when someone is talking to them.
This is one that will stick with me for sure.