Is it permissible to separate engaged couples due to expatriation, or to beat a daughter, imprison her, and prevent her from communicating with others, or for brothers to beat their sister merely based on suspicion? And is it justifiable to issue a general judgment about an entire country based on a small percentage of its inhabitants?

A guardian (wali) cannot prevent his ward from marrying a suitable man (kuf') if she consents to him, unless there is a valid justification. It is not permissible for the father or brothers to beat a girl to punish her for her desire to marry a suitable man or due to suspicions about her conduct. It is also incorrect to generalize a ruling about the people of a country based on the behavior of a few individuals among them. A difference in country does not negate suitability (kafa'ah). The questioner is advised to turn his heart away from this girl and seek a righteous woman for marriage.