Are dreams and the hearing of voices that herald the fulfillment of a specific matter, such as her marriage to a particular person, considered normal and acceptable things, and is her belief that these matters are the result of her supplication and persistence correct?

The effects of piety are clearly evident in a person's life, including the answering of their supplications. Imam Al-Bukhari narrated from the Prophet, peace and blessings be upon him, that Allah the Almighty said: "My servant continues to draw near to Me with supererogatory acts until I love him. When I love him, I am his hearing with which he hears, his sight with which he sees, his hand with which he strikes, and his foot with which he walks. If he asks Me, I will surely give him, and if he seeks refuge in Me, I will surely grant him refuge."