Hmm this is the 2nd post I've seen this week where someone is saying they either will quit or have quit due to the story being too difficult. It really surprises me, but I have a very strong RPG and MOBA background, so I think I might just understand the concepts min/max and incentive principle more than a casual player would. You should, as others have suggest, find a Free Company and look around online. There's great guides for every class and every dungeon. I'm sorry you're having trouble to the point of frustration, but that will bring an even greater resolution when you beat these battles. And you WILL beat them eventually!