don't try to slam slavation down their throats or else they will never except it. you've done all you can, you've told them about Christ and His love and what He did for each and every one of us. It's out of your hands now. You have done your job, now it is in the Lord's hands, well it was always in the Lord's hands, but if they are going to come and trust in Christ, you won't be able to do that. God is the only one who is able to turn a person away from his wickedness. the best advice i can give you is to keep trusting in Christ, be friends to them, and pray for them. Prayer is soooooo important. If it is in God's will for them to come to Him, then they will definitely, maybe not right now, but they will definitely eventually come to Him. John 6:37a "All that the Father gives Me will come to Me...." so just trust the Lord and pray for them, but at the same time don't try to slam slavation down their throats, you've done all you can do.