Thanks for your post. And aargh.. codependence is a really rough thing, because it can sneak up on you really easy. It masquerades as normal love and compassion, but in fact it's a strange form of mutual abuse. Lemme tell ya a story.
There was this guy I knew back in college. He was a cool guy, really fun to be around, that sort of thing. He also had some troubles, as everybody does, he was mostly blind, some mental illness stuff, but those things happen. So we started hanging out, and it was all good for a while. But almost imperceptibly, he started putting more and more responsibility for HIS happiness and well-being on me. I would give him rides and stuff, because who wouldn't, but in the end it basically became a full-time job trying to appease this guy. He behaved like a child. Screaming fits, suicide threats, all sorts of shit.. Oh, the stories I could tell you about the demands that he made...
And all of it reinforcing the 'saviour' role that I had cast myself in. (I used to be really bad about trying to save people, but in fact it's just a form of manipulation to satisfy my own needs.) Eventually the burden became too much to bear.. I was seriously going to kill myself if it continued... So I dumped him. Just stopped talking to him. He reacted predictably, more screaming fits and suicide threats, and then almost immediately attached himself to another member of our social group in the same way. He was an emotional vampire, you see. He didn't know it, and certainly wouldn't have been happy to find out (because he was definitely not a NARC) but still.. he would devour your life if you let him..
Why have I said all of this? Because that's what co-dependence is all about. Two people, both of whom are troubled, usually with abandonment issues from caretaker failures of varying levels. (I say failures, because my parents certainly didn't "neglect" me in a criminal sense.) So generally one of them will be the child, and another the caretaker. And that child will ride the caretaker into the ground. I know I did, until my wife kicked me out (so glad she did, best thing that ever happened to me). But it couldn't have happened if she hadn't stepped into the caretaker role.
And it can happen to anybody, because everyone has some sort of impetus to care for others, and be cared for in return. That's just natural. But it can become pathological really easy.
I can't say that the things that I've been doing would work for everyone, largely because I live alone. So I have to take care of my own stuff, laundry, cooking, finances, loan payments, doctors.. All that stuff. Taking all that responsibility on for myself has kept me from going CODA on my parents, or other friends. Everybody just handles their own business. That might be helpful.