Plan A: Check with the local authorities, and a good lawyer, and see what the requirements are to have him declared an "emancipated minor".
If he qualifies, set him free.
Free from the confines of living in YOUR home, by YOUR rules.
Plan B: Make a novena to Saint Dymphna, patron saint of those with mental disorders.
https://www.catholic.org/saints/saint.php?saint_id=222
Plan C: Stop trolling R&S