Praise be to Allaah.
It is haraam for a man to be alone with a woman who is not his mahram, even if that is for the purpose of treating her with ruqyah by reciting Qur’aan, because the Prophet (peace and blessings of Allaah be upon him) said: “No man is alone with a (non-mahram) woman, but the Shaytaan is the third one present.” Even more serious and sinful than being alone with him is your staying overnight in the house of that man who is a stranger (non-mahram) to you, and staying in his house for a number of nights and days, and being alone with him. These are means that lead to evil and corruption.
Any Muslim woman who has done such a thing has to repent sincerely from that, and not go back to such evil deeds.
And Allaah is the Source of strength.