Here are a handful of articles that are useful in uncovering Narcissistic and co-dependent relationships:

How Narcissists Form Abusive, Co-Dependent Relationships

The Co-Dependent Enabling Narcissistic Cycle: Initial charm, increasing criticism and abuse, contrition and apology, restitution and bribes to “win” the victim back, repeat pattern.

The Co-Dependent Coercive Narcissistic Cycle: Initial charm, increasing criticism and abuse, coercion (threaten to withhold emotional, psychological, sexual, material, or financial support), gain compliance through duress, brief period of calm, repeat pattern.

The Co-Dependent Guilt-Beating Narcissistic Cycle: Initial charm, increasing criticism and abuse, profess disappointment and blaming the victim (“I’ve done so much for you, and this is what I get in return!”), gaining compliance through eliciting partner’s guilt, brief period of conciliation, repeat pattern.

What all three co-dependent narcissistic cycles have in common is that, in each case, the victim is enabling her or his partner’s narcissism (narcissistic supply), while the narcissist is enabling the victim’s codependency/victimhood.

Can a narcissist change for the better? Perhaps. But only if he or she is highly aware and willing to go through the courageous process of self-discovery.