Prohibited Marriage

Marrying a Non-Muslim Who Has Inner Faith in the Islamic Beliefs

Salam Alaikum, Dear sir, I am a girl aged 29years old. I am leaving and working by myself overseas far from my family with my youngest sister. I met a gentleman who wanted to marry me. He is an arab like me and we are on good terms. However, he is an Arab Christian. I told him that a muslim lady is not allowed by religion to marry a non Muslim even if he is Christian. I love the guy and he loves me and we do not want to be together outside marriage. He is willing to marry me according to our Sunnah, and convert to Islam to make that marriage happen but he is not going to let go of his Christianity as it is not easy to forget about his roots especially that he believes in his religion and is a real practitioner. He used to go to church and do all the Christian related worships. We tried to get separated but I seriously cannot do without him ?and every time we get together again?I have great hopes that he maybe open to Islam and to the right path but I do not know how to do that especially that I do not want to be misunderstood that I am doing that just for the sake of marriage. Please advise me how I should approach him and what should I do? Would I be considered as kafera if I accept his conditions and accept to marry him? How can I help him to convert to Islam and can our marriage be the first step to such hedaya? I do not want to do something haram and at the same time I cannot live without him despite my perpetual attempts to get apart. i am torn between my love and my feeling of guilts...i am lost and i am unable lately to concentrate in my work. We are living in world in which it is no longer easy to find the right husband and as girls we tied out with our trditions which look at 29years old girl as an outcast if she doesn't get marriage althought this is something in the Hand of God. Pls help me as i do not want to make mistakes at this age. thank you