I quit a few months ago and couldn't be happier with my decision. Unfortunately, I require Facebook for work. The company I work for pretty much uses Facebook to run the business. We have several apps, developer apps etc.. We also use Messenger for communication. Deleting my account would essentially be career suicide so I had to find other ways to escape.

How did I do it?

• Delete the Facebook app and sign out of iOS level Facebook integration, this stops typical daily notifications.
• Messenger app stayed to retain chat functionality.
• Install Facebook's 'Pages Manager' app to give me access to some page stuff I need to do my work.
• Install 'Social Fixer' browser plugin on ALL computers/browsers that I use. This plugin allows me to heavily customise the Facebook experience, I can hide lots of stuff, distractions and even disable comments, likes, shares, etc.. One cool thing about this plugin is custom CSS. This is really powerful and aids hiding things like the timeline which is ultimately the biggest distraction.
• Disabled email notifications and as many other notifications as possible. Can be done from Facebook Settings.
• Make your profile look dead... Remove all photos, videos, recent posts, tags, personal info. You can also hide friends, prevent posts on your wall and make lots of tweaks that limit how people can contact you, the second biggest distraction.
• Have a little willpower. It's very easy to undo any settings change and even easier to disable 'Social Fixer' so a little self-restraint will be needed.

Doing the above allows me to keep Facebook to go about my work, keep in touch with clients and colleagues and still have easy access in an emergency. I can still log in at any time and see notifications but are now so rare it barely matters, but still come through for things like event invitations (I recently got invited to a wedding party that I may have missed if I simply deleted my account).

I feel like it's the best of both worlds. I went into a little more detail here