We have two weddings to celebrate with our family and friends who live in our home countries and make it convenient for our guests from USA and the diaspora. That being said, there is no expectation to come to both weddings. Guests from Biljana’s side are primarily attending the Macedonian wedding, and guests from Momchil’s side the Bulgarian one. 
Most international guests are traveling somewhere in Europe before or after the wedding for personal vacation and are adding a leg to Skopje or Varna. 
Skopje is a relatively small airport with daily connections from Istanbul (Turkish Airlines) ,Vienna (Austrian Airlines), Zurich (Swiss Air), Frankfurt (Lufthansa) among others.

Sofia is a major airport with many connections. You may land in Sofia and we can organize 3 hr drive to Skopje. Sofia - Varna has several flights a day. Turkish Airlines has daily flights to both Skopje and Varna, and has daily flights from Houston to Istanbul. 

Varna airport is also relatively small and mostly seasonal airport. With that said there are many many low cost European carriers that fly into Varna and most of them have no affiliation of any kind with the Major US airlines.

If you decide on both weddings, this translates to is a reservation that will most likely be split into 2 parts:
- Part 1 - US (San Antonio or other US City) to a major European City

The recent Condor flight from San Antonio to Frankfurt might be the logistically simplest way of getting to Europe from SA.

- Part 2 - Major European city to Skopje, Sofia, or Varna