I think I might feel that this is a personal rejection.
-When you and your DH were dating
, she made you pay for your own tickets. So, at that point she was organized enough to ask you in advance to see whether you were available before she made the ticket purchase.
-Now that you and he are married, she no longer pays for either of your tickets.
-She does pay for the tickets for the SOs of her other children. She manages to coordinate the plans well enough in advance that she can get committments from the SOs.
-She claims to be purchasing tickets for the family, but leaves the two of you out.
Is there some way of conveying to Albina that
1: it is rude to "bait and switch" with people by making it sound like it's a treated/ hosted event, when it is not
2: it is rude (and hurtful!) that she makes it clear that we are the only relatives that she is charging for the event
3: it is outrageous to complain that she "never gets to see her family" when we decline these pricey "invitations"
You can't tell her it's rude, but you can be direct in telling her that it is hurtful for her to imply that she is hosting you, when that's not really what she's doing. You can tell her that it is hurtful for her to tell you about what she is doing for the family, but to never include you and your DH in that definition of family.
I would be very direct about that last one. "If you really wanted us to join you, you would ask us before the tickets were purchased so that we could all sit together. Since you consistently ask us to join you at the last minute or after you have puchased tickets, I don't appreciate the guilt trip when you are clearly not prioritizing spending time with us."
Many of the PPs are advocating asking "how much", but I think it would be more effective to ask "have you already purchased your tickets," since that is the criterion that you are really looking at. If you were to decline after she told you the cost, then it appears that you aren't going because the cost it prohibitive. If you consistently decline when she tells you that she has already purchased the group tickets, it gives her a better clue that you won't go if she doesn't include you when buying seats (even if you do have to reimburse her).