Do you mean financial codependency? I've always tried to stand on my own two feet first, and then incorporate the boyfriend factor to what I have. I got my own job, my own circle of friends, my own life. I got my own house, my own car...etc.
If you actually mean emotional codependency, well...that is another ballgame. I don't think there is an answer to this. When you fall in love, you fall in love and no matter what you 've learned or what people tell you, you voluntarily remain as blind as a bat.
I can only wish you luck and to hope that this guy is a better one!