Choosing Abraham as an idiom is related to the Old Testament Patriarch Abraham who made love to his maid Hagar when his wife did not conceive. After his wife conceived he abandoned her and her son Ishmael.
As an idiom it means abandoning a significant other for the sake of family interests.
Example
In my life, if I am going to take up a new career in South East Asia, I won’t be a choosing Abraham.
We come across many choosing Abrahams in our life.
