Don't blame the work. That doesn't help. If you don't know how to balance your life then don't blame your job. It's not the job or the boss, it's your process that stinks.
If your work process was designed about 3 years ago, and you still do things the same way that you did 3 years ago, then you are on the edge of becoming a Neanderthal.
Once, it took a thousand years to see change on the planet. Now it's daily and soon it'll be hourly. If you're not evolving your process the first sign will be "Work Life Balance will go out the door."
Working harder to get things done went out about 10 years ago. If you are still working long hours to get your work done, you're a self proclaimed antique even if you're 18.
Here are a few modern day suggestions to evolve your process.
1. Work in chunks
If you have a 5 hour job to do, eat, drink and then go to it. Lock yourself away. Don't stand up or pee (joking) until the job is done. Einstein used to lock himself away for three days to do inspired work. He knew that it takes about 30 minutes to get totally into something and about 10 seconds for an interruption to send you right back to the uninspired state.
2. Don't Edit
Head thinkers edit everything. Head thinking leaders edit what they write, what they say, what they feel, what they think, what they do - they even edit their strategies over and over and over. Editing means "not inspired" - or "not in the Zone" Modern work practices don't edit. They spend time getting balanced, healthy and in a good space and then do it once, and do it un-edited.
3. Don't Kill Yourself Yesterday
If you blew a fuse yesterday it's going to cost you heaps today. So, instead, either don't blow a fuse yesterday or accept that you blew a fuse yesterday and don't expect too much today. Don't be blindsided by tiredness that makes your decisions and thoughts today absolutely crappy - don't trust yourself the day after the night before... go home and take a jog instead.
That's it. And if you are an employee rather than a self employed individual, then this balance thing is going to be even more critical because unlike an entrepreneur you don't have the luxury of choosing to work odd hours to suit your balance process. You'll need to be even more disciplined.