LTR tells me about one of her favorites movies. When I tell her I haven't seen it, she says she wants to watch it with me. I don't agree to it, but we keep talking about it. Later that night, I get the urge to watch it, and so I do.

Today, when I told her I watched it and enjoyed it, she gets upset with me. I try to maintain frame, explain why I watched it, and after she's still mad, I tell her if I had known she'd have such a strong reaction, I wouldn't have watched it. But I don't apologize. A few hours later, we're texting and she's still upset. I ask her about it and she says, "Well next time when I tell you I want to do something with you, don't do it without me. Especially if it's important to me. Also it would help if you apologized."

I'm still struggling with a lot of beta tendencies, am still learning how to be RP. Should I apologize in this situation? Am I at fault? How would a man handle this situation?