She Admires His Boundaries
She knows that space and time are necessary sometimes for everyone, and he deserves his boundaries to be respected without question. This respect makes her understand his individualism and her willingness to honor that.
She creates space and, thus the relationship finds a good equilibrium by giving equal security to her partner to feel at home. It is her respect for the boundaries he requires that creates trust around him to spend time with her and builds a healthy situation in their relationship.
