Everything you Need to Know about Narcissists, Psychopaths, and Abuse - click on this link: http://www.narcissistic-abuse.com/faq1.html
So, the narcissist's aggression wears many forms. The narcissist suddenly becomes brutally "honest", or bitingly "humorous", or smotheringly "helpful", or sexually "experimental", or socially "reclusive", or behaviourally "different", or find yet another way to express his scathing and repressed hostility. He often labels such thinly disguised aggression: "tough love".
The narcissist's favourite sadistic cocktail is brutal honesty coupled with "helpful advice" and "concern" for the welfare of the person attacked. The narcissist blurts out - often unprovoked - hurtful observations. These statements are invariably couched in a socially impeccable context.
Another favourite trick is to harp on the insecurities, fears, weaknesses, and deficiencies of the target of aggression. If married to a jealous spouse, the narcissist emphasizes his newfound promiscuity and need to experiment sexually. If his business partner has been traumatized by a previous insolvency, the narcissist berates him for being too cautious or insufficiently entrepreneurial while forcing the partnership to assume outlandish and speculative business risks. If co-habiting with a gregarious mate, the narcissist acts the recluse, the hermit, the social misfit, or the misunderstood visionary - thus forcing the partner to give up her social life.
The narcissist is seething with enmity and venom. He is a receptacle of unbridled hatred, animosity, and hostility. When he can, the narcissist often turns to physical violence. But the non-physical manifestations of his pent-up bile are even more terrifying, more all-pervasive, and more lasting. Beware of narcissists bearing gifts. They are bound to explode in your faces, or poison you. The narcissist hates you wholeheartedly and thoroughly simply because you are. Remembering this has a survival value.
(From the book "Malignant Self-love: Narcissism Revisited" by Sam Vaknin - Click on this link to purchase the print book, or 16 e-books, or 2 DVDs with 12 hours of video lectures on narcissists, psychopaths, and abuse in relationships: http://www.narcissistic-abuse.com/thebook.html