I can provide some general insights into narcissistic behavior, but please keep in mind that each situation is unique, and I cannot offer a definitive answer for your ex's specific actions.
Narcissists often exhibit impulsive and self-centered behaviors, including quickly moving on to new relationships after a breakup or discard. There are a few potential reasons why your ex narcissist got engaged to his new supply within months of your discard:
Need for validation: Narcissists have an insatiable need for admiration and validation from others. Jumping into a new relationship or getting engaged shortly after a breakup can be a way for them to seek validation and feel desired.
Fear of being alone: Narcissists often have a fear of being alone and may rush into new relationships to avoid facing their own insecurities or inner emptiness.
Love bombing: Narcissists are known for their "love bombing" tactics, where they excessively shower their new partners with attention, affection, and gifts during the initial stages of the relationship. This intense love bombing can create a sense of false intimacy and commitment early on, leading to quick engagements or even marriages.
Idealization of new supply: The new supply (the person the narcissist is currently dating or engaged to) may be idealized and put on a pedestal during the initial stages of the relationship. The narcissist may believe that this new person is "perfect" for them and rush into a deeper commitment.
Avoiding emotional pain: Engaging in a new relationship quickly after a breakup allows the narcissist to avoid facing the emotional pain and consequences of the previous relationship's end.
Control and manipulation: For some narcissists, getting engaged quickly may be a way to exert control and manipulate their new supply. It can create a sense of commitment and obligation, making it harder for the new partner to see the red flags or break free from the narcissist's influence.
Remember that engaging in a new relationship quickly after a breakup is not limited to narcissists, and people with various personality types may do so for different reasons. Additionally, labeling someone as a narcissist should be done with caution and preferably by a mental health professional, as narcissism is a complex personality trait that requires proper evaluation.
If you have recently ended a relationship with a narcissistic individual, it's crucial to focus on your own healing and well-being. Seek support from friends, family, or a therapist who can help you navigate the emotional aftermath of the breakup and build healthier relationships in the future.