Could I still travel to see family in other states?

Yes, of course. You would still visit family across the line, the same way people cross between neighboring countries with close ties every day. The crossing would run on an agreed border arrangement built to keep it smooth.

Crossing a friendly border is routine

Neighboring nations with deep family and economic ties keep their borders easy to cross. Over time you would carry a Texas passport or travel document, and the Texas-U.S. crossing would be designed to be as seamless as possible for families and commerce.

The relationship is built to stay close

A negotiated, peaceful separation keeps Texas and the United States closely connected, because both sides want trade flowing and the crossing calm. Visiting relatives, going to a wedding, taking a trip, all of it continues.

The bottom line

You can still see your family in other states. The fuller answer on passports and the border crossing walks through how it would work.