Can an adulteress repent, and is it true that one never forgets their first love?

Adultery is a grave sin. Whoever falls into it must repent, and repentance is possible and actual for both the male and female adulterer. For Allah's mercy is vast, He is the Forgiver of sin and the Accepter of repentance. Part of complete repentance is avoiding whatever might lead to the indecency again. As for first love, a person may forget it, especially if it was forbidden and they have repented from it.