I stopped using the harmful part of Facebook, ie the newsfeed, which is designed to create an addictive behaviour, using the following technique. On every single post in my newsfeed, I tell the application I no longer want to see content from the source. It takes some weeks to dry up, but you end up with an empty page. You still get notifications related to your events, group activities, and you can still use the messages. By the way, here's another tip, if you want to read and send messages on mobile without installing the app: use mbasic.fb.com instead of the default m.facebook.com URL.