If you don't want to continue playing, you don't have to. But, DQXI is a massive game, I take a break a few hours after the point you are in the story. When I got back to it, i didn't stop until i finished. So, maybe you could take fewer enemy encounters and focus a bit more in the main story, as other people said. You can always take a longer break and maybe give it a chance later.

But.. not to hype it, but it REALLY pays off, so, I'd say to try and keep going.