Certainty of this kind does something practical, whatever you believe about its source. People who expect warmth approach differently. They start the conversation, they assume the invitation was genuine, they don't read a slow reply as a verdict.
That alone changes the sample. Half of who ends up in your life is decided by who you gave a second chance to.
The other half is subtraction. Believing that good relationships are still coming makes it easier to end one that has been quietly costing you for two years, because you stop treating it as the last available option.