What is the way to get rid of attachment to a foreign girl, knowing that I am married, and I cannot complete the marriage with this girl, nor end the relationship with her?

The reason for the questioner's predicament is his disregard for sins and his failure to obey Allah's commands, such as lowering the gaze, guarding one's chastity, and abstaining from zina (unlawful sexual intercourse). Satan gradually led him astray until he fell into this forbidden relationship. The cure lies in obeying Allah's commands, such as lowering the gaze and guarding one's limbs, seeking help through patience and prayer, and seeking refuge from Satan through remembrance (dhikr) and reading the Quran. The forbidden relationship with the girl must be severed, and all means of communication with her must be changed. The best aid to steadfastness is accompanying righteous people and shunning bad company. The self is like a millstone: if you do not occupy it with truth, it will occupy you with falsehood. So, fill your time with what benefits you. Attention must be paid to the regulations concerning permissible and impermissible tawassul (seeking nearness to Allah through an intermediary).