How can I guide a friend who evades and refuses to commit to hijab, and avoids talking to me because of it?

A Muslim should be a sincere advisor and a lover of guiding others, as the Prophet, peace and blessings be upon him, said: "Religion is an-Nasihah (sincerity/advice)," and "None of you truly believes until he loves for his brother what he loves for himself." To invite girls (to Islam/righteousness), one must follow the methodology of the Holy Quran with wisdom and good admonition, and debate in the best manner, without harshness that causes aversion, while utilizing influential means such as tapes and religious lectures, remembering that guidance comes from Allah alone.