What is the remedy for frequent sexual thoughts accompanied by psychological instability, and the inability to fast often due to physical weakness?

The solution lies in adhering to the path of the Sharia, by observing the obligatory duties (Fara'id), increasing voluntary acts (Nawafil) and fasting, striving in supplication (Du'a) and imploring Allah to avert evil and indecency, associating with good people, and occupying oneself with what benefits in religion and worldly matters to avoid idleness.

One must also guard one's thoughts and immediately repel evil ones, and focus on reflecting on what is beneficial, such as contemplating Allah's names and attributes, the meanings of the Quran, and the Hereafter.

Psychological instability is treated by increasing one's devotion to Allah, finding comfort in Him, and attaching one's heart to Him, while knowing that Allah does not waste the efforts of those who sincerely strive against their selves, in accordance with His saying, the Almighty: "And those who strive for Us – We will surely guide them to Our ways. And indeed, Allah is with the doers of good." (Al-Ankabut: 69).