I cannot re-stress enough that before you lay down boundaries such as communicating through an app and no longer allowing him/OW access to your property, you should speak to a therapist and have them point you towards all available resources to help you know all your rights, protect all your assets and form a safety plan.
Boundaries for people like this are seen as antagonistic. And they don’t differentiate between small and large; the way they respond to a blown out light bulb, a leaky pipe or toxic mold in a home is the same: they burn the whole house down.
I once told my former H to leave his financial disclosure form in the mailbox, not to enter our former shared home. It was a reasonable request given his treatment of me, and it was made in a very calm, respectful manner. He responded to that by leaving an unsigned, incomplete form in the mailbox, draining accounts and vanishing. That’s just one example. The punishment will always far outweigh the “crime” of refusing to be abused any longer. I didn’t know then that boundaries have to be the SECOND step. The first step is preparing for all possible responses to the boundaries and, as much as possible, having protections in place for any scenario.
Please talk to a therapist, document these incidents, and find out how to protect both your physical self and your future security.
The desire to be loved is the last illusion. Give it up and you shall be free. ~ Margaret Atwood