Often times, people expect one thing in their lives to satisfy every need and want. For ambitious and goal oriented people - they expect their career to satisfy EVERY need they possibly have. That unfortunately is never the case, no ONE person, or ONE job, or ONE thing in life can satisfy every part of who you are. When a person expects this and then is faced with the reality that IT (trading on one's own in this case) didn't provide eternal happiness, but instead that balance and diversity are key to being happy, it is quite difficult for many to adjust to and accept.
With that said, I think its important to take a step back and look at your entire life, not just TRADING. When our lives become one-dimensional, as is often the case with traders, we tend to project all our unhappiness and discontent onto that one thing (since it's really the only thing in our lives). It is critical however, not to give up on or walk away from something that you do enjoy, but that doesn't satisfy ALL of your needs. You may be giving up on something that you truly like, and is very good for you...
Let's assume you do enjoy trading... but that it doesn't satisfy EVERY need.
What needs does trading satisfy, what needs does it not satisfy? Personally speaking - What makes you happy? What makes you unhappy? Does trading satisfy some of these needs? Does trading satisfy any of your needs?
Finally - Consider other ways to get ALL of your needs met; those needs that aren't fulfilled by trading can be fulfilled countless other ways - aside from getting a 9-5.
If you're lonely - then are there ways to stimulate your social life without getting another job? Join a club, volunteer, match.com, bars, art classes, go back to school part-time, church... etc. etc.
Ultimately finding pleasure and happiness in other aspects of your life will help to re-energize you, help you to rediscover what you do enjoy about trading, and help you tolerate those small things about trading that do get old... i.e. the grind.
If on the other hand, there is nothing but trading that you enjoy, you just wanted to to make $1M - than find somehting else.