It is funny how as much as we think we know ourselves and the boundaries we have set up, there always comes a time when some aspect of our life we hold so dear is put into question. We may have felt so seated, so grounded in our ways that we thought "this part of my life is set for good."
But it is not possible. The great teacher will always come around and knock you off your seat. It will come in the form of a human or situation that will throw you for a loop. And when you return to your seat you will be changed. And the other person or the world will be changed as well.
But what we forget sometimes in this scenario is that the thing that we must learn is often set forth by our own selves, like a lesson plan that we are unknowingly committed to follow. We set up the classroom, go to school and return with new knowledge of life, a new understanding of the boundlessness of love, or something else quite important and vital to our personal evolution.