That observation is accurate and also somewhat deflective. The wry framing — “such is the price of fame,” as if this were a minor inconvenience — is the kind of self-protective humor that Nicholson has deployed throughout his public life, a conversational style that keeps the emotional center of a statement slightly removed from direct view. He is not saying it did not matter. He is managing how much he shows that it did.
Anjelica Huston, who was in a long relationship with Nicholson that began around 1973 and lasted through 1990 — meaning she was present in his life at the time of the discovery — has offered her own perspective in her memoir Watch Me, published in 2014. Her memoir is a source for her own memories and interpretations, which should be understood as exactly that: one person’s experience and reading of another person’s life.
Huston’s account of Nicholson in that period, and her interpretation of his emotional life more broadly, provides context but not direct access to his inner experience. She was observing him, knowing him intimately in the way a partner knows a person, but the interpretations she draws from that observation are hers. Any reading of her memoir that converts her observations into confirmed facts about Nicholson’s psychology would be going further than the source supports.
What emerges from Nicholson’s own statements, taken together, is a picture of a person who absorbed the discovery, verified it, adjusted his understanding of his family, and continued. He continued being who he was. He continued his career. He continued his relationships. He did not spiral, did not retreat, did not become publicly defined by the revelation. He made peace with it, as people make peace with difficult facts, through time and through the continued accumulation of other things in a life.