Stuck int he middle of 2 friends (complex)?

So my best guy friend LOVES my best gall friend. My gall friend is taken and in a complex "relationship", I asked her if she would ever date him(my friend who shes friends with) and gave him the news that she did not like him like that. I did this once before, about 3 months ago but he decided to continue pursuing her. He finally gave up after I told him this time and is giving her the silent treatment in cl. Today I asked him if he wanted 2 hang out after school and he said no, although he hung out with his other guy friend and is treating him normaly(i asked). It has been 3 days since I have given him the news and the is acting like a baby about it. What should my approach be?