Does the girl with whom the questioner committed adultery and lost his money for her sake deserve a bad recompense from God, especially after she left him despite her promises to him?

The relationship between young men and women is impermissible in Islam, and what is called a "love relationship" is a custom of the disbelievers. The questioner has erred by committing zina (fornication/adultery) and persisting in a forbidden relationship, wasting his life and money therein. He must make sincere repentance by abandoning the sin, cutting off the relationship with the girl, feeling remorse, and resolving not to return to it. He should hasten to marry a chaste Muslim woman of faith.