Narcissists do tend to surround themselves with others who help them maintain a high or perfect image of themselves as perfect, successful, etc. They like everyone around them to make them look good. Another narcissist might seem to help maintain that image, so it would be possible for a long-term relationship to be formed on that basis. However, there are potential problems. Neither would like it if the other appears to show them up. Also, the inflated self-image is an illusion and underneath that narcissists are vulnerable and defensive. Any relationship based on false selves anf false images (which could apply to any personality disorder or other mental disorder also) probably won't be a very satisfying relationship. If you can work towards revealing more of your real self first, you will have better relationships.