I've always insisted on finding work I enjoy greatly. When I've found myself complaining endlessly about it, I've figured it's up to me to make whatever changes I need until I stop complaining and start enjoying again.

Sometimes the joy doesn't happen right away, and it's necessary to work for a while accumulating the skills or documentation that will qualify you for the fun stuff. Mostly it's possible to make even the early stages themselves interesting or enjoyable, but that's an internal process--it's done by changing your attitude. That's a key point: it's not usually the work itself, but the attitude you bring.

In my earlier career in the construction trades, the learning curve involved lots of backbreaking labor. In middle age I switched to a professional career which required 5 years of sitting in classrooms and taking frequent exams. In neither case was the preparation/learning phase exactly a barrel of laughs, but both were endlessly fascinating and "fun" in their own ways.

I'll acknowledge that the world economic crunch has made a lot of this more difficult. Most of us came of age during remarkably slack, easy times (although we may not have recognized this until it was over). Those days are largely gone now. I'll also acknowledge that the kind of mobility across different vocations I'm describing is more common in the USA than in Europe or the UK. But still....

Executive summary: I believe you're supposed to be reasonably happy, doing something you love doing. I believe it's up to you to find or create the job, lifestyle, and inner strength which allows that to happen. I'll add that it's a rare individual who'll accomplish this while living rootlessly on the road for long stretches. You might need to discover this last bit on your own.

Mark