Everything looks great for him, but Maria is terribly worried. Richelieu's demise means that Chevreuse can disclose his marriage without fear. When he points to Maria, Chalais’ world begins to collapse.
Despite the positive aspects of his situation, Maria is anxious about the consequences of Richelieu's demise.  Chevreuse can now openly admit his marriage, and when he does so by pointing to Maria, it causes significant damage to Chalais' life.