My dad is an alcoholic, but my mom left him when I was young. She never sought any kind of help for herself, thinking she had "gotten rid of her problem." So I think most of my codependent behavior was learned from her, though I certainly saw it in my dad's family. But that was the mean kind of codependency, where people hold grudges even after the other person is dead, and do or say anything and everything to degrade them in life.
My mom was always incredibly helpful, solving other people's problems (many of which are things she simply identifies as a "problem" whether the other person sees it that way or not, sigh). She feels really good when she thinks she has helped someone in need (even if she is the only one to see that need and the person is actually annoyed or uncomfortable with her interfering).
I was much the same way, especially intimate relationships. I was also promiscuous as a teen and young adult, giving away sex and trying to get love. Plus I had no real idea how to set boundaries about my body and telling people (especially men) no actually scared me.
Here's to hopefully breaking the cycle for my kids. No matter where I went or who I was with, only I could "get rid of my problem." Still working on that, ODAT.