I got married abroad and I think she is being unreasonable and possibly deluded. If you choose to marry in a far flung location you have to accept that people can't or choose not to attend.
I am from the UK and DH from a European country where I didn't speak the language. With elderly parents both sides (his never leaving the village, let alone the country) and neither of us religious, we decided to go to Vegas - just the two us - not sad or indulgent just our choice.
My family is complicated half of it is NC, five of his family members would have meant over 20 children under 8. I love a good wedding but had never wanted the big, grand princess for a day celebration.
In the end his best friend and wife and my best friend guessed what we were doing. (both childless at the time with disposable income) and they wanted to come - to be honest it was a better time with them there, we had such fun.
The reason we didn't tell people before hand is because we couldn't afford to pay for them to attend and didn't want to put pressure on people. We had postcards made of a wedding photograph and sent one to everyone we knew so it arrived home before we did.
A few people said they would have attended if they had known. The immediate family were fine about it as we had picked a neutral place. 14 years and two kids later, we have no regrets - we don't feel like WE missed out.