At its most severe, jealousy illustrates our intolerance for boundaries and separateness from those we love. Our desire to possess our partner is inherently frustrated by the immutable fact that we are two fundamentally separate (thought interrelated) people.
You can see emotional fusion in the mayhem we commit in relationships,
in our inability to separate, to leave well enough alone, when we are on the edge.
Emotional fusion is so tenacious, it's borrowed functioning.
Differentiation refers to your core sold self and the level of development you can maintain,
independent of shifting circumstances in your relationship.
You can appear more differentiated than you really are, depending on your marriage's current state.
Borrowed functioning artificially inflates or deflates your functioning.
Your "pseudo self" can be pumped up through emotional fusion,
which makes poorly differentiated people hang onto each other.
Two people in different relationships can appear to function at the same level although they have achieved different levels of differentiation.
The difference is that the better differentiated one will more consistently function well even when the partner isn't being supportive or encouraging.
Differentiation is the ability to maintain your sense of self when you partner is away or when you are not in a primary love relationship.
You value contact, but you don't fall apart when you are alone.
Passionate Marriage - David Schnarch, Ph.D.