Sometimes combat gets a little weird. Target and me have range damage, fighting back to back and still hurting each other. He runs a little further away and keeps attacking. I face away and still throw ice forward but damage him behind me.

I can also nudge/move and the enemies adjust their position to remain away from me for these range attacks.

I have fire melee attack and I am running into this same issue, it is not on every perp it just seems to be on certain ones though. I have been fighting some level 9's and one kept doing the same thing to me run right past me and I would shoot behind me to kill him regardless of how many times i would try to turn around to hit him.

This happened to me on my melee scrapper. But when I went to loot the body, nothing was happening. It almost seemed like what my screen was showing for me as the enemy position was incorrect. I noticed this sometimes happening when I try to melee an enemy, and my toon does nothing. Sometimes I have to run away, then re-engage to actually be considered in range of target. Whether or not this is due to a graphical location error, or something else, is not known.