I encouraged my girlfriend to get a separate cellphone. As a kindergarten teacher it doesn't seem obvious, it is incredible how much they plan and discuss after hours. Now she switches off her phone and enjoys her leisure.
Month ago I built my own android app that automatically switches on airplane mode whenever the display switches off (and vice versa). Made in 10 minutes with Tasker, it's even in the play store.
Since then I really enjoy life again without any notifications, it's just wonderful.
They removed access for 'insecure apps'. Go to your Google account > Settings > activate 2 factor authentication and get an individual password for each app.
Source: Had to do this to all my superb python bots that we using mails for error reporting.