I am so glad that things are going well. I remember your concerns about the trip and how to approach your extended family.
One thing that I have found, is that we accelerate our concerns and fears before such a new adventure and meeting in our sobriety, but when we look back, it just wasn't that hard nor hurtful.
Hopefully, you have gained from this realization and can use it in the future when new meetings and trips are on the horizon.
Do not know what part of Mexico you are vactioning, but I go each year to the East Cape of Baja for a week of relaxation and fishing (mid-way between La Paz and and Cabo). Far more of a family orientated experience than the constant party of Cabo.
Jerry