Is he an active JW? Does he bring up quotes from the bible? IF so, he has already sinned. I can tell you these are the worst kind. He will pretend he is very religious to all around him, but he will cheat on you in the future (he has already). I believe he is just using you.
I, baptized a catholic, married a JW. Before and durring the marriage I always supported her in her religion, but I never joined. Before we married she had lied and decieved me many times, and, being blinded by love I forgave her. Like you I was very much in love with her. I must admit that it was the worst thing I ever done, marry her.
It was not the religion because I am very open minded and do accept that everyone has their own beliefs, it was her continuous lies. Because of her lies before our marriage, I never trusted her durring the marriage and this is what saved me, yes because I was able to see all the lies she would make durring the marriage. I live in Canada and she lives in the Philippines, so I was lucky to see right through her before I brought her to Canada. You can read my story at www.openletter.bhmo.ca.
If I were you I would walk away from this man. I do know what it feels like to be really in love with someone. You may forgive him today, but you will make your life miserable if you marry him.