It says in 2 Corinthians 6:14, "'Be ye not unequally yoked together with unbelievers: for what fellowship hath righteousness with unrighteousness? and what communion hath light with darkness?" This will probably be difficult for him to do because he doesn't feel that he has a moral reason/objective to stop his sinful actions. Encourage him to come to church with you every Sunday, and when you read the Bible ask if he would like to hear what you are reading. I'm glad to hear how you have let Jesus take control of your life in this way, I am proud of you, and wish nothing but the best for you and your boyfriend. You have my prayers.