I recommend you say off Valtrex for several weeks, and the next time you get apparent gum inflammation, see your primary care provider (or your dentis)
for HSV testing from the inflamed gums. If postive
for HSV-1, you will have proved me wrong -- but I would be very surprised.
In general, suppressive therapy is not commonly used for HSV-1. The main reason is to prevent symtomatic outbreaks, when those outbreaks are particularly severe or frequent.