Redd,
I keep seeing this question as I scroll down. It boggles me that you seem so absolutely distraught in your current situation, and then ponder if co-dependency is so bad. Your situation sounds pretty bad.
Your question seems comparable to a diabetic asking if eating too much chocolate is really all that bad. Well, yeah, it kinda is.
Depending on the approval of someone else, particularly someone whose life is completely out of control and unmanageable, for your happiness and sense of well-being seems like it would always be a bad idea.