All perfect praise be to Allaah, The Lord of the Worlds. I testify that there is none worthy of worship except Allaah, and that Muhammad, sallallaahu ‘alayhi wa sallam, is His Slave and Messenger.
According to Sharee‘ah (Islamic law), the husband is required to keep his wife in an acceptable manner or release her with good treatment as Allaah The Almighty says (what means): {Either retain them according to acceptable terms or part with them according to acceptable terms.} [Quran 65:2] But to neglect the wife and abandon her as it was stated in the question, then this contradicts the good manners enjoined by the Islamic religion regarding dealing with the wife. For more benefit, please refer to Fatwa 88304 about observing good treatment with one's wife.
On the other hand, divorce cannot be proved by the mere claim of the father that his son has divorced his wife; rather, a proof for this is required or that the husband acknowledges that he has really divorced her.
As for your question whether this divorce is final, then we do not understand what you exactly mean. What we can say is that you are still married to your husband unless the contrary is proven.
Anyway, it is more appropriate for the questions that include claims and require proof to be referred to Sharee‘ah-based courts so that the judge may look into the matter and give the suitable judgment, especially that the judgment of the judge is binding unlike the Fatwa of a Mufti and thus it is not enough to depend on a Fatwa in such matters.
Allaah Knows best.