Mexico is a big country and it's incredibly diverse, so violence along the US border won't have any effect on your vacation in, for example, the Riviera Maya any more than an earthquake in California would affect people in Chicago. Most of the violence that has taken place recently is due to conflicts between drug cartels and the Mexican authorities. As a tourist, you are in little danger of having trouble as long as you follow common sense safety precautions and don't get involved with drugs.
Research your destination and choose a place that feels right for you. There are plenty of places in Mexico where you can have a tranquil, relaxing vacation. You can also significantly reduce your risk of being a victim of crime by following these important safety tips: