One-to-One optional relationship with both ends optional and both FKs

This is what I'm doing: 1-to-1 Optional Relationship with EF Code First

And this is how my relationships are set up:

public class Review {
    [Key]
    public int ReviewId { get; set; }

    public virtual Payment Payment { get; set; }
}

public class Payment {
    [Key]
    public int PaymentId { get; set; }

    [ForeignKey("Review")]
    public int? ReviewId { get; set; }
    public virtual Review Review { get; set; }
}

    public class ReviewConfiguration : EntityTypeConfiguration<Review>
{
    public ReviewConfiguration()
    {
        // One-to-One Optional
        HasOptional<Payment>(s => s.Payment).WithOptionalDependent(s => s.Review).Map(s => s.MapKey("PaymentId"));
    }
}

And I only ever receive ONE of the keys mapped as an optional FK; the other is never valid:

Why am I misusing this?

I've seen several strange, hacky methods that don't fit what I'm looking for, like making empty lists, etc. I'm trying to find the perfect strategy here; it has had to exist, right?

Update

I now use the above, however it really stinks because I have to hunt for the [pseudo-FK] ReviewId every time I need to see or delete the Review when I have the Payment on hand.