All perfect praise be to Allaah, The Lord of the Worlds. I testify that there is none worthy of worship except Allaah, and that Muhammad is His slave and Messenger. We ask Allaah to exalt his mention as well as that of his family and all his companions.
The thoughts that unintentionally come to the mind of a person and he does not indulge in them in principle do not harm him. The same applies to the dreams that a person has while sleeping.
Therefore, there is no harm on this sister for such thoughts if she does not think about them intentionally or indulge in doing so. However, she has to repel these thoughts and seek Allaah's Help to prevent her from such thoughts which are a means of falling into sin. She has to continue performing Tahajjud [night] prayer and mentioning Allaah when going to sleep, etc… She also has to fast as much as possible as the Prophet said: "O young people! Whoever among you can marry, should marry, because it helps him lower his gaze and guards his modesty (i.e. his private parts from committing illegal sexual intercourse etc.), and whoever is unable to marry, should fast, as fasting helps him control his sexual desire." [Al-Bukhari and Muslim]
There is no harm on her to ask her female friends to seek a pious husband for her through their husbands and there is no harm on her, Inshaa' Allaah, to propose herself to whom she wants to marry, provided this takes place without raising suspicion or subjecting herself to be doubted. Indeed, a woman proposed herself to the Prophet so that he would marry her. [Al-Bukhari]
Allaah knows best.