How can one get rid of repeatedly falling into sin and repenting from it, while Satan continues to dominate and one feels a loss of sensation in the heart, despite loving one's wife and maintaining prayer and righteous deeds?

You can overcome the whispers of Satan by bringing your wife to you, or by traveling to her if you cannot bring her. If you are unable to do either, then you must fast, for it is an effective remedy for lowering and refining one's desires, as stated in the Hadith: "O young people! Whoever among you can afford to marry, let him do so, for it is more effective in lowering the gaze and guarding the private parts. And whoever cannot afford to do so, let him fast, for it will be a restraint for him." You must also strive against your soul and Satan by frequently remembering Allah, performing prayers, and reciting the Quran; as Allah says: "Recite, [O Muhammad], what has been revealed to you of the Book and establish prayer. Indeed, prayer prohibits immorality and wrongdoing, and the remembrance of Allah is greater." Moreover, sincere repentance is necessary, along with a firm resolve not to return to sins, and an increase in good deeds, as Allah says: "And establish prayer at the two ends of the day and at the approach of night. Indeed, good deeds do away with evil deeds. That is a reminder for those who remember."