In chemistry, debonding is a term used to describe a decomposition or dissolution reaction or that in which an atom, molecule, or species detaches from a host or surface. In human chemistry, the term is often used in reference to a relationship breakup or the process in which a person slowly begins to leave a structure, such as an infant detaching from a parent, a student leaving for college, a daughter leaving her birth family to start a family of her own, etc.  Technically, a breakup in an intimate relationship involves the a weakening of the human chemical bond between a attached pair A≡B of human molecules. The quintessential debonding process is a relationship break-up or divorce in which a previously attached structure, e.g. a couple AB or friendship, detaches where person A begins to separate from person B, as shown below:
AB → A + B (bond dissolution)
Debonding typically involves energy absorption, meaning that energy in the form of productive external work is being used up negatively in the relationship, often via arguments, and is thus an "endergonic process". 
One of the first to study the debonding process in human relationships was American sociologist Diane Vaughan as discussed in her 1986 book Uncoupling - Turning Points in Intimate Relationships. 
In relationships between a parent and a child, however, the a theory of "detachment" was outlined in the 1960s by British developmental psychologist John Bowlby and his associate British psychiatric social worker James Robertson. 
1. Thims, Libb. (2007). Human Chemistry (Volume Two), (ch. 14: "Bond Theories", pgs. 561-607). (preview). Morrisville, NC: LuLu.
2. Vaughan, Diane. (1986). Uncoupling: Turning Points in Intimate Relationships. Vintage Books.
3. Thims, Libb. (2007). Human Chemistry (Volume Two), (section: "Detachment", pgs. 595-96). (preview). Morrisville, NC: LuLu.