When people I meet learn I work from home, the common perception is that it's too easy to sleep in, or watch TV all day. The reality is the exact opposite.
Since 2005, I've worked from home as a full-stack web developer building some quite complicated sites. Imagine the following scenario.
You're half way through a 2 week project. It's turned out to be a larger job than you anticipated and you're stuck on a PHP problem that's taken up your whole day. You're starting to worry about missing your delivery date. Another client just emailed you requesting urgent changes to their site which will take you a day or so. They are expecting a call back. Several sites you manage need updates applied and there's at least a dozen unanswered emails in your inbox.
Your wife pops her head in your office. "Dinner's ready." (she's awesome). Is it that time already?!
There's no drive home. No soothing train ride. No winding down.
With a frazzled head still in work mode, it's a 30 second walk to the dining room. Through dinner all you can think about is your looming deadlines and all the work silently calling out to you from a few rooms away.
There's no time for TV or relaxing for you, Mr. I Work From Home.
If you're committed to your freelance business - and you should be - switching off is VERY hard when work is in the next room. That's why I often tell people working from home is the same as living at work.
Two things to do to combat this.
Unless you have an urgent task pending, try to finish by 5:00pm every night and get some exercise. A 30 minute session between work and family time makes an incredible difference to your frame of mind. Without it, I'm in work mode all night and can't focus on anything else.
Turn off your work phone and avoid email from Friday night to Monday morning. Clients will email you and call you at all times. You've got no idea. If you happen to see an email on Saturday morning requiring your attention you'll find it hard to think about anything else until you've attended to it. The reality is, it can wait to Monday and your client will understand.