Serious advice needed about a relationship/family?

I had a boyfriend for 5 months and he really made a mive impression on me so we are both smitten with each other. My family hate him because he is a tad y and has done some very stupid things concerning me in the past (nothing like hitting or stealing). Eventually they told me that I had the choice of either staying with him and being kicked out of my family home, or never see or have anything to do with him ever again and continue to live in the family home. Of course with a reality check I chose to contintue living with my family. But I am still in love with my ex and now we have secretly started meeting up and discussing getting back together in secret. But because of world war 3 that kicked off about me being with him before, I am really scared about getting kicked out. He has somewhere for me to live if I do get kicked out, but I really dont want my family to hate me if they find out I am back with him and have done it behind their backs. I am almost 18 and so is he so I guess I am almost legal to make my own decisions. But I really want to be able to have the best of both worlds, having him as my partner, and my family there supporting me and being happy for me. But I know that in reality I can only have one and not the other. Someone please advise me as this is a really important issue to me. Thank you.