I like that you asked her to put herself in your shoes - kind of reminds me of the ending line from the Bob Dylan Positively 4th Street song.

I can understand your feelings as Mexico was where the one night stand(s) occured. This seems like both a trust issue and the feeling that you are not part of her plans.

How well does your W converse in Mexico as I think you said her english and spanish was not that good. Have you ever considered taking a trip to French Guiana together?