Sincere souls will certainly overcome all difficulties in the long run. Lord Sri Krishna Himself gives assurance in the Gita - na hi kalyana krt kascit durgati gacchati. "A sincere soul will never suffer degradation". When one can really detect one's defects it is a good sign because it proves he has contact with real knowledge, however faint it may be. Otherwise ignorance could not be realised as ignorance. So, don't be disheartened. Actually it is not possible for us to eradicate in one day our attachment to worldly objects and ideas which we have inherited through cycles of births and deaths. Those inherited ideas will have their reaction for some time through inertia. For example, if we switch off the fan, it still moves for some time due to inertia, but its speed will be gradually diminished and it will stop. If we try to control the senses artificially through austerity it won't have an abiding effect. In devotional spiritual practice more stress is given to positive practice than to negative i.e. we are to rouse up the eternal natural function of the real self which is pure love to the Supreme Godhead.