struggling with something so amazing

what's the problem with being happy? what's the issue with finding something you care about? if you thought, "well nothing, why is that a problem?" then Id tell you that I agree, because I do. But I can't seem to understand why other people don't. I found somebody, I found this girl, actually I befriended her about three years ago after a horrible situation in my life, she helped me pick myself back up, she helped me regain my smile, she's always understood my dry sense of humor and unfunny remarks. Three years ago, I found her. Since then, we've been best friends. Hanging out when we can and messaging eachother dumb memes at random intervals. Inviting her to my hangout seshes and discovering new things we can talk about. Well, our friendship ended about two months ago, specifically on April 10th, 2025. That's because we, including our friend group, went and saw a movie. We all had a wonderful time, laughing, spilling popcorn, yelling at the screen (respectfully). Afterwards, we had to go home, my other friend, D, drove me and my friend home. The car ride was long, cold, and very crammed due to the other passengers. I, almost instinctually, rested my head on her shoulder, placing my hand on her knee. It's like time froze as we sat there in the backseat, I couldn't even hear the music at that point, just her breathing, my racing heartbeat. She rested her head on mine, it stayed like this for a while. Our friendship ended, because she finally, after three years, became my girlfriend. I have never felt so hopeful, so happy, so blissfully dumb to be where I am now.   

But...theres a problem, my beautiful girlfriend, is trans. She's been out since high school, my parents knew. I have always supported her, always bought her fem clothes, taught her how to do makeup, how to do her hair. She's perfect to me, so willing to learn new things, so prideful in herself, so authentic...but my parents...they hate her. They hate who she is, that I'm dating someone who's so happy, because that's what I see it as. I barely get to see her anymore, I can't call her at my moms house, I can't even drive to visit. Best part about all this is, Im an adult, yet here I am, having a middle school esk relationship with my parents. So yeah, what's the problem? Why is it so wrong to be happy? Somebody tell me the answer, even though I know for a fact that you would be wrong.