Trying to help a friend?

i have a friend who is VERYnayib about relationships & me & my other friend would like to open his eyes. he is 18 and his gf is 16, first off this girl went out wit his cousin tried to sleep with him but he denied her because hes 15 and i guess is a late bloomer cus doesnt look interested in . they broke up a week later cus of the same reason. after that she tried getting at my friend and they became friends with priveleges. once he misst work because she told him she would go to his house and have with him if he stayed home. well, he stayed home and she didnt even give him a call and we laughed at him and it was funny blah blah blah. well then it got worse because they started going out and she slept with him like 3 weeks later and she told him she was a virgin which she clearly wasnt cus she already told us she slept with half of the world. NOW he is mad in love with her missing work calling in sick and puting pix in myspace of her.. can anyone help me?