What's the best word that captures "a simplified representation of a complex process"?
Solution 1:
Given your example sentence
"Alex uses her feelings about her mother as a ______ for her relationship with all women."
I would suggest
template n
2. anything that determines or serves as a pattern; a model: You can use my notes as a template for employee evaluations.
TFD Online
So:
"Alex uses her feelings about her mother as a template for her relationship with all women."