What is the ruling on suicide as a means to stop committing sins, and does Allah forgive one who does that due to their repentance and desire not to disobey Him?

What the questioner mentioned about suicidal thoughts is a wicked whisper from Satan. A person who commits suicide exposes himself to the wrath of Allah and His painful punishment. The Prophet, peace and blessings be upon him, threatened such a person with eternal damnation in the fire of Hell, as stated in the noble Hadith.

He should seek refuge with Allah from Satan and the evil of the commanding self, and frequently recite the supplication: "O Allah, Knower of the unseen and the seen... I seek refuge with You from the evil of my soul, and from the evil of Satan and his polytheism."

The blasphemous thoughts he experiences and his hatred for them are a sign of the soundness of his faith, because his aversion to speaking such words and his fear of them are clear signs of faith.

The cure for repeated sins is repentance, frequent seeking of forgiveness, and following bad deeds with good deeds, while hoping for Allah's mercy and forgiveness.

The questioner's statement, "I sold my life in exchange for stopping disobeying Him," is a grave error, as suicide is a transgression against Allah's command and is worse than other sins.

One must submit to Allah's ruling regarding the prohibition of suicide and face life with sincere repentance and turning towards Allah Almighty.