It's not codependence, but there is a psychological phenomenon at work.
I mean, we're all human, with our mix of emotions, prejudices, idiosyncrasies, etc. I just think it's silly to start painting a number of SP owners as "codependent" and stating that this is what explains their comments on this thread. I think we're being pretty casual about how we use certain medical terms that apply to some serious illnesses, and it's potentially pretty insulting.
To put it another way, does it elevate the level of discourse and provide useful information to help resolve the problem with Mikhail, or otherwise inform? No.