What should I do about my feelings for a young man I don't know, given my refusal to be involved in a relationship outside of a legitimate, شرعي marriage?

A woman's adherence to God's boundaries and her avoidance of unlawful mixing (ikhtilat) is a grace from God, and she must remain steadfast in this. A girl's attachment to a foreign man is impermissible if it is initiated by her. However, if it occurs without her seeking it, she is not blamed, as long as it does not lead to something forbidden or prevent an obligation, and its ultimate goal is marriage. If a girl wishes to marry a young man, there is no harm in sending someone to propose that to him, provided that the engagement and marriage are through her guardian (wali), and the suitor remains a stranger until the marriage contract is concluded. If the marriage does not take place, she must strive against her own desires to remove her attachment to him, seek Allah's help, supplicate to Him for a righteous husband, and be patient in this, for Allah does not waste the reward of those who do good, and what Allah chooses is always best.