Our Gemara on Amud Beis discusses the way in which arrogant men at first charm women during courtship but eventually disappoint:

מִשֶּׁרַבּוּ הַיְּהִירִים הִתְחִילוּ בְּנוֹת יִשְׂרָאֵל לְהִנָּשֵׂא לִיהִירִים שֶׁאֵין דּוֹרֵינוּ רוֹאֶה אֶלָּא לַפָּנִים

From the time when haughty people proliferated, the daughters of Israel began marrying haughty men, as our generation looks only at the face, i.e., the external aspects of a person, and ignores the inner aspects of a person.

אִינִי וְהָאָמַר מָר הַאי מַאן דְּמִיַּהַר אֲפִילּוּ אַאִינָשֵׁי בֵּיתֵיהּ לָא מִיקַּבַּל שֶׁנֶּאֱמַר גֶּבֶר יָהִיר וְלֹא יִנְוֶה לֹא יִנְוֶה אֲפִילּוּ בַּנָּוֶה שֶׁלּוֹ מֵעִיקָּרָא קָפְצָה עֲלֵיהּ לְסוֹף מִיתְּזִיל עֲלַיְיהוּ

The Gemara raises a difficulty: Is that so? Do women wish to marry arrogant men? But didn’t the Master say: One who is haughty is not even accepted by the members of his household, as it is stated: “The haughty man abides not” (Habakkuk 2:5)? “Abides [yinaveh] not” means that even in his abode [naveh], he is not accepted. The Gemara explains: Initially, she jumps at the chance to marry him, because he appears to be a great person to her, but in the end, once she gets to know him, he is demeaned in her eyes.

The sages seem to be aware of the psychological dynamic where a grandiose or narcissistic person appears charming and romantic in the early stages of a relationship, but eventually insecurities and insatiable need for validation, degrade into hostility and control. What are some of the red flags and warning signs that Prince Charming might be a dark knight instead? According to researchers Strutzenberg, Wiersma-Mosley, Jozkowski, and Becnel (“Love-bombing: A narcissistic approach to relationship formation”, https://www.researchgate.net/publication/317663551_Love-bombing_A_narcissistic_approach_to_relationship_formation ) “Love Bombing” is considered an important sign that narcissism may be at play instead of enduring love.

• Love-bombing was identified as the presence of excessive communication at the beginning of a romantic relationship in order to obtain power and control over another’s life as a means of narcissistic self-enhancement.
• The praise from the narcissist to their relational partner may be flattering at first, but over time, becomes overwhelming and sometimes debilitating. 
• It is assumed that whether consciously or not, the narcissist is making an effort to secure their place as the most important person in their significant other’s life. 
• Narcissists ultimately praise themselves by way of praising their significant other in hopes that their partner will return the praise, but eventually the narcissist’s excessive flattery and need for affirmation will result in the end of a relationship when it becomes apparent that the misplaced affection reaches no further than the narcissist’s affection for him/herself (Campbell and Foster, 2002, Narcissism and commitment in romantic relationships: An investment model analysis. Pers. Soc. Psych. Bull. 28:484-495.)
• Narcissism is defined by the American Psychiatric Association’s Diagnostic and Statistical Manual of Mental Disorders (5th ed., 2013) as holding beliefs about being special or unique and the assumption of only being under- stood by special or high-status people or institutions, as well as requiring excessive admiration, experiencing frequent envy, and displaying arrogant or haughty attitudes and behaviors. 
• Narcissism can present itself in multiple different ways such as “one who aims to enhance ego, pursues success, acts autonomously and chooses short-term goals that will result in admiration from others” (Rogoza et al., 2016). Narcissism has also been described as being characterized by entitlement in relationships, self-indulgence, self-assuredness, and disrespect for the needs of others, which leads to both aggressive behaviors and the generalized devaluation of others (Brown et al., 2009; Paulhus, 1998; Rogoza et al., 2016).
• The narcissist’s ideal mate is someone who is highly positive, admires them, and enhances their self-worth either directly through praise, or indirectly by association as in that of a “trophy spouse” (Campbell et al., 2002). Narcissists often see relationships as a “forum for self-enhancement” (Buffardi and Campbell, 2008). 
• Narcissists are generally perceived as exciting (Foster et al., 2003), socially confident (Brunell et al., 2004), and likeable in initial interactions (Oltmanns et al., 2004). Though these attributes are attractive in the beginning, they fade throughout the course of the relationship, revealing the tendency of narcissists to use relationships as a means of self-enhancement (Campbell, 1999). In turn, the “victims” of relationships with these initially likable nar- cissists find themselves stuck with psychologically controlling, non-committal partners, often characterized by “game- playing” in relationships (Campbell and Foster, 2002).
• Researchers have identified that narcissists consistently use social relationships for three main purposes: to regulate their personal self-esteem, to create a positive self-concept, and to produce a self-gratifying personal construct (Buffardi and Campbell, 2008; Campbell, 1999; Campbell et al., 2006; Morf and Rhodewalt, 2001; Raskin et al., 1991). Essentially, narcissists rely on their interactions with others to determine how they feel about themselves. For that reason, individuals with low-self-esteem will engage in reassurance-seeking behaviors in romantic relationships, especially when they are depressed (Campbell et al., 2002). This desire for reassurance sought through romantic rela- tionships is more than likely to involve love-bombing behaviors, because of the narcissist’s desire for affirmation by means of association.

These are insightful explanations of the internal dynamics and external behaviors of narcissists in romantic relationships. However, caution is necessary so as not to over diagnose. In the words of the pioneering psychoanalyst, Freida Fromm-Reichmann, the difference between mental health and psychopathology is only a matter of degree. Who can say about themselves that we don’t seek admiration, reassurance and self-esteem from those we love? Who can say we do not seek regulation and soothing from depression and fears through romantic engagement? To the contrary, one who seems impervious and invulnerable might be too insecure and afraid to admit the need for basic attachment. Rather, one must look at the overall feelings and patterns. If there is initial excitement followed by eventual anger when you are unable to continuously praise or please or if you feel uncomfortable and choked by the excessive flattery and attention, or if you see extremes in mood and unpredictability, these are indicators that something is not quite right.