This appears to me when I am using VHE or Celestial - the damage returns to me. Not sure about the Talisman the other team weared, probably there is a way to get behind Van Helsings passive. When I attack VHE or celestial in PvP the other team arrives no damage. Passive had not been disabled, as far as I had seen this. Enemies in PvP using VHE or celestial usually take no damage when they hit my starfire... so, it is a mysterium to me as well.
To be honest - I donīt use it while attacking very often, but my defense team (except that event team I use at the moment) wears it and I donīt have many losses on it - probably a PvP-defense-only-Talisman
if you can't avoid hitting the character with the starfire, make sure you hit softly on it..this won't kill you
Van Helsing and Celestials negate the damage done by starfires