Your right to be concerned. I think its wonderful you are addressing it. I recently read an article that explains the problems people with this condition encounter in a relationship.
It states:
Narcissists are often exciting, charismatic, and a bit dangerous, which can make them attractive to us. Their grandiosity can be expressed through breathtaking romantic gestures. These reel us in and keep us hooked.
When the less attractive side of narcissism -self-centeredness, lack of empathy, and hot-cold behaviour- emerges. Here are some of the classic behaviours of a narcissistic partner.
Appears charming and interested in a relationship, but becomes selfish, manipulative and controlling, seeks superiority or dominance over a partner.
Employs game playing tactics, being unfaithful, unattainable to maintain power and independence in a relationship.
Is rarely found to be involved in a long-term relationship.
Often attracted to partners with low self-esteem, who will be more likely to feel at fault and blame themselves when the relationship goes wrong.
May swing from placing you on a pedestal to behaving as if you mean nothing to them.
Unable to recognise their behaviour, which is upsetting to other people, and therefore unwilling/unable to change. It is this trait in particular that makes it almost impossible to sustain a loving sharing relationship with a narcissist.
Do you want to hear more? If not, I hope that helps you to understand how change can help you find and keep someone to love. Narcissism is human, and we must avoid condemning or idealising it if we want to understand this very real and painful condition.