To tell SIL we won't go to her wedding?

[NoIHaventChangedMyName]

If they book it in the exotic location they want? It is simply beyond our means and I have already basically said as much. If they proceed and book it in AIBU in that we won't go?

Just tell her, very nicely but firmly, that if she decides to have her wedding in this far-flung place, you can't afford to go. Period.

I wouldn't go to a wedding abroad if I didn't want to visit that country and make a holiday of it. If you dont have the money for it then you cannot go...its as simple as that.

If people choose to get married abroad, they either pay for their guests to go, or they expect that they may not have any guests at the wedding.