I work a full-time job, so when I come home, I have only a few hours during the work week to write. I try to utilize my time as efficiently as possible. The weekends are great because I get to hole up in my writing room and spend hours with my characters, honing my craft, and untangling the stickier bits of my plots.
Honestly? Having at least one person out there who enjoys my book, who might walk away from it a little happier, with a little more hope in their life, or even just coming away with a good laugh. If someone shares my characters' journey and enjoys it, that's success to me.
Take the time to let yourself rest. Allow yourself to have a day or two where you don't write. Breaks aren't just necessary, they're healthy for good writing. Also, go on vacation and travel. Not only do you get a chance to let your batteries recharge, trips are amazing fodder for story lines and plotting!