I can understand your concern. At the present moment, I would suggest that you go slow as you have not met this person but only talked to him over the phone. You are still young and studying; involvement in such relationships may lead once again to another negative experience, which may affect your studies adversely. There is no harm in continuing correspondence with this person without committing yourself to anything until you meet him and also make your parents meet him. The question is not whether you can trust, but whether you can make a proper judgment about his personality and him as a person, because (1) you have not met him and (2) you are still not ready enough to make such judgments.
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