I would've appreciated a fair warning as to your current relationship with my brother. I did not expect you at the party, much less you dating Charlie. You could've mentioned something at the Ministry when you came to edit my letter, the other day, so it wouldn't have been such a shock surprise. As it stands now, Ron is furious at me for excusing myself early from his birthday party and now I must go about setting things right. And you should know by now that my dealing with my family is often akin to walking on egg shells.
If your intention was to send mixed messages, then congratulations, you succeeded.