I have an entity user which has a many-to-many association with itself

a User is a tenant to a List<User>
a User is a Renter to a List<User>

I load a Renter, and I initialize its List<Tenant>
Then at some point he wants to remove oneself from the Tenant, so I have this function:


public void removeOneselfFromTenant(User tenant, User oneself) {

// initialize Tenant List<Renter>, as it is lazy loaded
getSessionFactory().getCurrentSession().lock(tenant, LockMode.NONE);
Hibernate.initialize(tenant.getRenterList());

// remove the association from both sides
tenant.getRenterList().remove(oneself);
oneself.getTenantList().remove(tenant);

// update the Renter who is mapping the association
getSessionFactory().getCurrentSession().update(oneself);
}

But I get a
org.hibernate.NonUniqueObjectException: a different object with the same identifier value was already associated with the session

which makes sense I believe, because when initializing the Tenant List<Renter>, I load the List<Renter>, which contains the same record from the Renter already present (oneself)
they are different object, but they correspond to the same record (thus the same id)

so I don't know what I should do, I understand that to delete the association, I need to delete the Tenant from the Renter collection; and the opposite
I guess that I should do something like loading all List<Renter> in the Tenant object EXCEPT the Renter which already exists in the session (oneself)

Is there a better way I'm supposed to do?

Thanks!