Rationally, she knows it is simply a strong psychological attachment, a biochemical process in her brain based on the repeated release of oxytocin and subsequent reward triggered by their shared experiences. When she detaches from the rational, however, in the safety of solitude or the surrender of fear, the connection between them feels like a living entity of its own. A web, intricately woven into each of their bodies and psyches, pulsing with sensation and energy. In the moments when one or both of them is in danger or their partnership is threatened, and those threads seem stretched so thin they nearly snap, she feels with visceral terror that their breakage would be akin to the marrow being stripped from her bones, or the blood sapped from her vessels. And every time the threads do not snap - every time the web pulls one or both of them away from death and back toward each other, against all rational odds - the fibers strengthen and branch into new points of connection, reinforcing the link between them and drawing them further into each other.
This deep comingling she senses with him is both exhilarating and terrifying. She has never been so completely interdependent with another person. Not in a practical sense (although they've saved each other's lives more times than she can count), but in the sense that her concept of safety, of reality, of "rightness with the world", is fundamentally linked to his presence in her life. Often, when he looks at her, she sees the same in his eyes: a naked and irreproachable need for her, for them together, balancing on a knife's edge with the panic of what losing each other would mean. The web between them is both strong and brittle, able to withstand countless near-death trials, while simultaneously made fragile by its sheer essentiality. They both sense this. They are intermittently familiarly brutal and scrupulously tender with each other, heavily treading the safe ground of investigation and debate while moving gently through demonstrations of their care for each other, acknowledgment of the web itself. As if they both fear that to probe it too deeply may cause the fatal rupture.