What is the conflict in the novel nausea by jean-paul sartre?

Ideologically, it's between man and nothingness. In the story there are some other conflicts, but I'm burdened by not seeing them with fresh eyes. Anyway, the nausea Roquentin feels results from him not seeing any meaning in objects or the endeavors of those around him. His memories and struggle to piece together history prove equally meaningless to him, and when he looks at certain things they sometimes look "strange." Probably, he's seeing on some level that they don't have any essence. Although it's a great narrative, you also have to realize that Nausea is a philosophical novel--and the premise of Sartre's philosophy is, in response to Plato, that existence precedes essence.