I stopped DP from singing.
DP has an awful voice. Actually, that's not really true. DP has a perfectly nice voice, she's just utterly tone deaf. I used to quite often hear her singing to herself and think "That's quite nice", and then ask her what it was and it'd be some song that I know, but there's no way I'd have recognised it from what she was singing. The tempo is wrong, the notes are wrong, the words are often wrong too. If she's singing along to something, or along with other people, then oh god it's painful, she can make a room of people all fail to sing Happy Birthday because they're all trying to somehow get in sync with her. Basically, there's something in between her brain and her voice that is just utterly broken.
And this intrigued me. I like weird brain stuff. I've got aphantasia and face blindness and its so weird knowing that everyone has this superpower that I don't, and that I and most of humanity have one that DP just doesn't have. So I'd talk about it lots, it made me laugh in the same way it makes DP laugh when I desperately struggle to work out who I'm talking to, only to realise half an hour later it was my Step brother. I'd gleefully tell people about DPs singing. It wasn't mean, at least it wasn't meant to be. I loved her, and part of what I loved about her is this utter inability to do something that to me seemed so basic.
And then one day we were in the car and a song DP loves came on the radio. And I realised DP wasn't singing along to it. And then I realised I hadn't heard her sing anything in months.
"You don't sing any more."
"No, I don't"
We sat in silence for a minute, while the sheer horribleness of what I'd done sunk in, and then the apologies started. I must have gone on for 15 minutes or so, apologising profusely, telling her how bad I felt, how I never wanted her to stop singing, begging her to not stop on account of me.
And she accepted my apology. But she didn't start singing again. That was a decade ago, and it's only been in the last 6 months or so that I've caught her singing. At first when she thought noone could hear her, and more recently when we've been in the car together. I've not said a word. I don't dare, in case it stops her again.
We have a wonderful relationship. I adore her, and she claims to adore me. We have the sort of relationship I'd be intensely jealous of if I wasn't in it. But I will always be the man who stopped DP from singing, and thats something I will never forgive myself for.