Headed North on RT28 in moderate traffic just before the bridge leaving Prince William County; Entering Fairfax County Me - Traveling in #1 lane (fast lane) Her - Traveling in #2 lane (slow lane) #2 lane traffic slows as cars turn into shopping center headed to meat market store. Without warning the Silver VW Jetta driven by a female driver in her late teens early 20’s cuts in front of my car in the #1 lane forcing me to swerve LEFT into the turn lane and get hard on the brakes!! Had I not swerved to avoid the Silver Jetta she would have smashed my front passenger fender and door area. I was taught to always do a head check BEFORE changing lanes.