Just when we think we've finally gotten used to things in this time...
As for Regulus, do you remember someone telling us at Prongs' wedding that the wedding isn't really for the bride and groom, but to give their friends and family the chance to celebrate? The bond itself is just about the two of you. No one begrudges you that. I'm glad you found someone to drag your arse out of bachelorhood.
This is one of those big life events that people want to share with you, not because they want to interfere or judge. But, because they love you and want to just celebrate you. It feels a little like being cheated out of the chance to see something special, to share just a little bit of that happiness with you.
Regulus has been been left out of so much of your life already. You're his only brother and he doesn't get to share that with you now. Even I will get to share it with Prongs, at least.
...if he doesn't decided to elope the second time. He and Lily aren't married, did you know? I found out when I confirmed that I'm not married either. They'll have to do it all over again.