When I was sixteen, I fell in love with my best friend and we started dating. Her father was an ex-marine with serious temper problems and very clear ideas about the kind of people worthy of hanging around his kids, and I wasn't one of them. He hated me. It didn't help that he was a homophobic psycho and if he'd found out about us, she'd have been sent to some kind of camp and my parents would definitely have been alerted way before I was ready for them to know.
We had to hide our relationship from both our families for more than two years. On several occasions she got into trouble for something unrelated and her parents' preferred punishment was to tell her she couldn't see me/hang out with me anymore. We made it work around all the restrictions, but it was a state of constant paranoia - no matter where we went together, someone who knew her family could see us and we'd be screwed. We couldn't hold hands in public, couldn't kiss at the movies. One of the only times we had truly to ourselves was on Sunday nights when her parents dropped her at church for youth group...and I waited around the corner til they left, picked her up and took her somewhere else. We'd go down the road a little ways, park by the train tracks and sit in the back of my Explorer for the precious hour we had, just cuddling and talking.
The relationship was incredible while it lasted, and in the terms of this question, it was successful; it didn't end because it was forbidden love, but just because we went to college and the distance proved too great. I'll always have fond memories of that time, even if it was unduly stressful. OP, I hope you find a way to make it work. I'm sorry for your troubles.