Gotta say, I'm not in DPS gear and it seems like I'm very hard to kill most of the time. There are a lot of games I die 0 times. I run with about 28.7k hp and around 1100 expertise. 30% defense rating 37% shield and 37% shield absorption unbuffed. The two things you want to be most worried about are HP and expertise. I got the highest hp armorings/mods/enhancements/augments possible for every slot. You also want to make sure that your defense is around 30% while doing this.
Well there is your problem.
Defensive stats (shield and absorb) are way too low. Even for pvp.
And with only 1100 expertise you're not doing yourself any favors.