Experience has taught me that people can change. Often they are reflections of their circumstances; people adapt to situations, and dynamics can remain static if the circumstances remain static, either due to external forces or the unwillingness of a partner to make fundamental changes in factors like availability or external commitments.
Circumstances can act as triggers. If one partner is chronically unavailable on some level, the dynamics that trigger obsession in the other will remain in place. Once the fundamentals change, it seems not only logical but inevitable that there will be a change in the dynamic, with the prospect of normalized relations a realistic possibility.
There is a difference here between conventional addiction theory, wherein the object attachment is to an inanimate, chemical “other,” and the realities of dynamic relationships between two human beings. The complicating thing about romantic obsession is that people can change, make promises, become available, or some other dynamic behavior, versus the chemical object that does not change its nature.
With people, you never know. With drugs and alcohol, you always know – after the addiction threshold has been crossed.