Somewhere along the line, we lost the ability to figure out what works and what doesn’t; how to avoid person-traps and generally stay on track.
There used to be a framework of how to make all the required decisions we make to stay more-or-less upright on that track. Choices come with rewards and consequences. Put mayo on your sandwich every day, you have a taste sensation that lasts ten minutes. Consequently, you notice after a few weeks that your pants are a little snug. While the timing might not match, the cause and effect certainly do.
It is the same with people. If I continually overlook the behavior of a woman who consistently flirts with other men when I am with her, then I will have to live with my jealousy. The choice is whether to break up, or accept that she will always flirt. Decide, young man, the outcome is yours.
In this case, the choice is more simple that you might think. She flirts. I become jealous. I cannot change her behavior. I must decide to stay dating her or not. No. We must part. (Unless I am forevermore willing to swallow my reaction, like an idiot.)
That’s it. The framework exists, but it is made of cold logical steel.