I like what AG said about usually being considerate not making it okay to NOT be considerate.
I also agree that going away - in itself - is not a red flag, but the fact that he *assumed* you wouldn't want to go is a problem.
That said, I think it's just time to set boundaries, not necessarily break up with the guy. He needs to know that it's not okay to make assumptions about what you will or won't do b/c that is bound to lead to problems later.
As for the dinner, I wouldn't take that too seriously. He invited you to go, and I'm thinking that these friends will be gone for a while, whilst he knows he'll see you in a week. I don't think it means anything about your importance to him (except in a good way, since he invited you).
It will probably be hard for you to separate how you felt with your former SO from this sitch, in the sense that it will be easy to read into his actions what might not actually be there, in a negative way. I know that I have a tendency to do that, and it is hard work to break that habit.
Nicola
Life isn't about finding yourself; it's about creating yourself My thread: Trusting God's Plan
