Yes. Personality disorders frequently overlap, and a person can meet criteria for both narcissistic and borderline patterns at once — clinicians call this co-occurrence. Traits also exist on a spectrum, so someone may show strong features of both without a formal diagnosis. What matters for you is less the exact label and more the pattern of behavior and how it affects your safety and wellbeing.
The personality disorders share features like unstable relationships and difficulty with emotion. Real people rarely fit one tidy box, which is part of why self-diagnosing someone from the outside is unreliable.
You can't control whether someone gets evaluated or treated. You can notice the pattern, name what's happening to you, and decide what you need to stay well.