Morphdom 

(verb) - The act of your significant other adopting your friends, using your vocabulary, and wanting to perpetually be attached to your hip.

Things were going great with Sally until morphdom set in.

Morphdom by zeboro January 11, 2012

morphomasochist 

Someone who compulsively ingratiates themselves through often self-punishing personal adaptations, usually for secondary gain.

As a masterful morphomasochist he got himself tight with the boss, thereby grabbing the power and control he craved.

morphomasochist by Dr Bunnygirl February 14, 2019