Does the repentance of one who repeatedly commits the same sin get accepted? And what can she do to earn God's pleasure?

Your friend's crying and remorse are evidence of her repentance, in accordance with the hadith (definition): "Remorse is repentance." The remedy for what she complains of is to hasten to repent whenever she falls into disobedience, and not to despair or give up hope. Even if the sin is repeated hundreds of times, and she repents each time, her repentance will be accepted and her sins will be expunged. Al-Hasan (definition) al-Basri was asked: "Does one of us not feel ashamed to seek forgiveness, then return [to sin], then seek forgiveness, then return?" He replied: "Satan would love to gain this from you; so do not tire of seeking forgiveness." And Shaykh al-Islam Ibn Taymiyyah said: "The servant is commanded to repent whenever he sins." Some said to their shaykh: "I sin." He said: "Repent." He said: "Then I return [to sin]." He said: "Repent." He said: "Until when?" He said: "Until you sadden Satan."