I think we’re overcomplicating things with all this “destiny” and “fate” mumbo-jumbo.
“Leia told me she sensed a different calling than a Jedi’s.”
It’s short, simple, and to the point. She had more motivation to focus her efforts on being a mother and political activist.
The thing is, that line ties up with the next one, where someone would come and finish her Jedi journey. I think the implication should be that she had to let go of that path, not that she just felt like doing politics over religion. At the end of her Jedi training she sensed that was not the path she was meant to take. It’s easy then for the audience to put two and two together, in that she simply went back to what she was good at, as she says in TFA. Her letting go of the Jedi mantle then comes as a result of her training and being in tune with the Force, and NOT as a rejection of it.