It sounds like your in an impossible decision. I'm not a very religious person so I can't give any guidance on what to do to satisfy your faith, but I have been in love before. I've loved two women in my life and honestly I still have feelings for both of them. The first was a girlfriend I dated when I was 18 who struggled with what sex she liked more. She eventually decided she liked girls more and broke up. There is nothing I can do to change the other person sexual preference. I just had to accept things won't work out and move on. The other women is my wife. I found someone else and developed a deeper and more rich love and relationship. In my opinion each time you fall in love it is its own experience and will fill different for each person.
Your family has put you in an impossible position, but at the end of the day you have to make a decision. It's not fair for you, but sometimes we get put into unfair situation. You can talk to your family and tell them how much this guy means to you. You can accept that this relationship with him won't work, or you can disregard your families wishes (and possibly faith) and pursue this relationship. You should weigh out this decision as it and try and come to terms with things. I hope you start to feel better and enjoy life again. There are a lot of people in this world and you could find something even better. I hope this helps.