Hey matey, I'll assume that you come from a WoW-like MMO background and it does take some getting used to the new combat style in GW2. While the controls feel deceptively similar to WoW-like games, combat plays out quite differently.
For the most part mobs are not supposed to hit you, so any major attack will be "telegraphed" and you are meant to avoid it either by moving out of the way or using your "dodge" charges. Combat is GW2, at least in the open world, is not so much about maximizing your DPS but outlasting your enemies.
I had a similar experience, coming from WoW, when starting with GW2 and found myself dying quite frequently. Once you get to grips with how the game "is meant to be played" you'll find that its not too hard at all. It's just a change of pace.
Amazing game overall!