Advice please

How do you cut someone off when you have kids and still live together? Before anyone suggests moving out, right now it's not a possibility because due to covid and the lockdown all house moves and viewings are being suspended although I am waiting on a phonecall the moment they start back up. Also living with family or friends is definitely out! At the moment it's not the living arrangements I'm concerned about, it's how to distance myself from the man that broke my heart that I need help with.