Sri Aurobindo
Letters of Sri Aurobindo
Volume IV - Part 3
The sex-impulse is the chief difficulty in your way and, if that were got rid of, it would make the ground clear for the sadhana in you to take a much fuller course. If it persists, it is because 
some part of your being still clings to it and your mind and will have remained divided and found some kind of half-justification for the continuance. The first thing is for the mind and also the higher vital to withdraw their consent altogether; if that is done, it becomes only a mechanical return from outside on the physical and finally only an active memory which will disappear when it is able to find no welcome in any part of the nature.