Staying alive is the hardest part of PvP. Killing people is easy, it's staying alive that's hard, especially for a RDPS who has always had a tank soaking up the damage. You're learning just how fragile you really are.
Some tips, in order of importance:
1. Use your range. Stay away, and hit from a place that's hard to get to. The ramps in Huttball are a ranged DPS dream. Expect to be constantly moving, and know the good spots.
2. Learn to kite. It's not hard. First you have to save your CC. Don't use it until someone is after you (Huttball excepted). When someone is coming after you, you should see them coming, because you are far away. Force slow them, and when they get close, Force Sprint to the opposite side of the fight. If they break it, use Whirlwind or Electrocute. Now you have separation again. If they come close again, use another CC. Always use your CC to get away, and you will.
3. Bubble yourself always.
4. Avoid getting hit with AoE. It's not hard, and it eats your health up.
Good luck!