How does the author illustrate the connection between Martin and Mariela in the story, M+M?

In M+M, Martin remembers Mariela writing his name on his shoes with a Liquid Paper pen and coloring it in with different colored markers. By writing his name down in her own handwriting, Mariela demonstrates that she is part of Martin’s identity, for his name is tied up with her actions. This blurring of identities between Martin and Mariela is dramatized through Martin’s imagined conversation with Mariela, for Martin cannot conceive of himself as separated from Mariela: he thinks of his actions as betraying her. Thus, through the act of writing, Mariela connects her world with Martin’s, even if their lives are not connected in reality.