How can one get rid of masturbation and sexual thoughts and whispers after repeated attempts to quit and failing?

A Muslim's feeling of guilt and self-reproach is the beginning of the right path, and the danger lies in the death of the heart that feels no pain from sins. One must sincerely turn to Allah and ask Him for well-being, be wary of stimulants of desire through which Satan gains control, and frequently remember Allah, for by His remembrance do hearts find tranquility. There are means that aid in steadfastness. One should reflect on the harms of masturbation and not despair of repentance upon returning to sin, for despair is a misguidance from Satan.