Resolve the database relationship cycle

In the database I have a model of kind:

The customer can either rent a car or rent out a car. As you see Car has OwnerID - customer who owns a car but at the same time customer can also rent a car from another owner so that in Order table he appears as User.
So how can I change the model to avoid such cycles and is it even possible?

Consider identifying (storing in tables)

• who the owners are and what they own, and
• who the customers are.

.

create table persons (
  -- I prefer "people". YMMV.
  person_id integer primary key,
  person_name varchar(25) not null
  -- Other columns go here.
);

create table cars (
  -- VIN might be a better choice.
  car_id integer primary key
  -- Other columns go here.
);

create table car_owners (
  -- Only car owners known to us can rent out a car.
  car_id integer not null
    references cars(car_id),
  owner_id integer not null
    references persons (person_id),
  primary key (car_id, owner_id)
  -- Other columns go here.
);

create table customers (
  -- Any person can rent a car. (But some persons are not customers.)
  customer_id integer primary key  
    references persons (person_id)
  -- Other columns go here.
);

create table rentals (
  customer_id integer not null
    references customers (customer_id),
  car_id integer not null,
  owner_id integer not null,
  primary key (customer_id, car_id, owner_id),

  -- Don't rent a car unless we know who the owner is.
  foreign key (car_id, owner_id)                  
    references car_owners (car_id, owner_id)

  -- Other columns go here.
);