I'm going to happy hour while me SO sits at home with a broken ankle.
How did your significant other break their ankle?
She was out shopping and tripped, fell and then broke her ankle. I'm sorry it happened to her, but I want to go out and have fun.
Oh no, I'm sorry your girlfriend is dealing with that. It's unfortunate that what happened, but it's okay for you to go out and have fun. Just make sure that you're still being supportive and understanding of what she's going through.
She wanted me to stay home, and I told her she could come out with us, but she declined.
Just because your partner has a broken ankle doesn't mean you can't have a fun time and go out. Especially since you offered to have her come with and she declined. Just be sure to still spend time with her and not to always leave her alone or she will resent you.