Hurted

I love a guy,mr.X...I love him so much...but, lately,I have heard a lot of bad "rumors" about him..he have went out with a girl..he just hide it from me..after i get to know about it, he said she is just like sister for him..when i see his handset,i saw some love messages sent by that girl..when I ask, he just ignore the question and starts new topic..after all, I get to know that he have ask one of his friend to spy on me whether I'm in love with any other boy..I'm very confused about our relationship..he was such a good boy ever before this..what should i do now???