Just remember, you don't know what's going on between the two of them this weekend. They could be fighting and having a crummy time cuz RC is thinking about you. His mom could be sabotaging their relationship cuz she prefers you
This weekend was set up long before you came back into the picture and would have been a difficult thing to cancel - don't fret about it. In fact, a dose of reality spending time together (instead of fantasy long-distance stuff) may just do their relationship in (one can always hope !)
So go out and have a good weekend and don't stress over it.