How can one discipline the self and convince it to definitively abandon a girl with whom the questioner previously committed fornication, despite his marriage to a righteous and respectable girl, and despite his knowledge that his wife is better than the previous girl?

The following advice is offered to help you overcome thoughts of a foreign woman after marriage:

1. Marriage is a commendable step to avoid Satan.

2. You must cut off thinking about her for your repentance to be sincere.

3. Remembering death motivates one to abandon forbidden acts; what if death comes while one is committing a sin?

4. There is much good in you; do not ruin it with a bad ending.

5. You have a lawful wife who is more beautiful and better; praise Allah and seek refuge in Him from Satan if he whispers to you.

6. Increase your supplications intensely in the last part of the night, asking Allah to free you from your current state.

7. Remember that such thoughts might lead you back to old sins, and fornication is one of the greatest sins after polytheism, with many negative consequences for one's religion, self, and the afterlife.

8. It is recommended to read the book "Al-Jawab al-Kafi li man sa'ala 'an al-dawa' al-shafi" by Ibn al-Qayyim.