If you believe you will really regret getting married overseas, don't do it. Put your foot down and tell people this is your wedding and you're doing it how you want.
That said, you can still have a small, intimate wedding at a resort or something in Mexico, the Caribean, etc. (Resorts such as Sandals include a free wedding if you stay for 7 nights.) You can still wear the traditional dress and have a lot of traditional aspects, but they do all the planning and you don't have to worry about your family interfering.
I plan on getting married overseas with immediate family (our brothers and their wives and our parents) only. My best friend will stand in for me and my bf's best friend, and their partners would be guests. I've never dreamed of the big, traditional wedding, so this is just the perfect, intimate wedding for me.
If you really think you'd regret not having a traditional, big wedding, sit down and talk with your family. Otherwise, go for it! I think you'll love a Mexican wedding.
Good luck!