I agree with this article - we can't know love if we haven't experienced it through another being. And the practice of receiving love from others and cultivating healthy relationships is important and is often left out of the self-love movement. BUT - we can also draw on our past experiences of love to cultivate love of ourselves in the absence of another being. It truly only takes one moment in our lives of feeling loved to learn how to love ourselves.
Also not sure why they threw that line in about co-dependence - the truth is a lot more complicated than that!
I am a Licensed Marriage and Family Therapist practicing in Carrboro, NC.