Being together with an atheist “updated”

Hi guys, I’m interested in what you guys think about my scenario. I’m a baptized Christian with a Christian family. Almost a year ago I met this amazing guy whom later became my first boyfriend, after we both realized we’ve been secretly in love with each other for months. I didn’t know about his beliefs until after we got together. He doesn’t believe in god and is pretty stubborn about it. He’s perfectly fine with me being Christian. But my parents and pastor aren’t happy about it. They think I won’t be happy with an atheist because our life together would be unbalanced. But he makes me so happy and he’s a wonderful person. Do you guys think it’s ok for a Christian to be together with a non Christian? If we’re getting married he said he’s willing to pretend to be religious for me but that’s just wrong.

Another problem is we’ve had premarital sex, and I believe it’s ok. My pastor and dad said it’s a sin and are confident I would not do it so I don’t know what to do. I do think two people have to commit to each other to have sex but we are committed and it does benefit our relationship. I don’t want us to get married because we want to get into bed. That’s the wrong reason.

Sorry about the rant but please give me some advice on what to do about my relationship and my family. I want to follow god and I really feel like god brought us together. I’m not willing to break up with him because of this.

Update: so I’ve told him everything and he said he’s willing to go to church and read the bible with me. He also said he’s no longer an atheist, more agnostic now and he’s willing to consider Christianity to lead a better life. I’m very very happy of course but my concern now is that he’s only doing it to make me happy and to please my dad/in order to be allowed to marry me.