public void SaveRecipient(Recipient myRecipient)
{
    if (myRecipient.RecipientGUID == Guid.Empty)
    {
        myRecipient.RecipientGUID = Guid.NewGuid();

        foreach (ContactMethod tmpCM in myRecipient.ContactMethods)
        {
            context.Entry(tmpCM.Type).State = EntityState.Unchanged;
        }

        context.Entry(myRecipient.LastModifiedBy).State = EntityState.Unchanged;
        context.Entry(myRecipient.Owner).State = EntityState.Unchanged;
        context.Entry(myRecipient.CreatedBy).State = EntityState.Unchanged;

        context.Recipients.Add(myRecipient);
    }
    else
    {
        var dbRecipient = context.Recipients
            .Include(a => a.ContactMethods).ThenInclude(t => t.Type)
            .Include(b => b.CreatedBy)
            .Include(c => c.LastModifiedBy)
            .Include(d => d.Owner).ThenInclude(o => o.Users)
            .FirstOrDefault(x => x.RecipientGUID == myRecipient.RecipientGUID);

        if (dbRecipient != null)
        {
            dbRecipient.FirstName = myRecipient.FirstName;
            dbRecipient.LastName = myRecipient.LastName;
            dbRecipient.Company = myRecipient.Company;

            foreach (ContactMethod tmpCM in myRecipient.ContactMethods)
            {
                var dbCM = dbRecipient.ContactMethods.FirstOrDefault(x => x.ContactMethodGUID == tmpCM.ContactMethodGUID);

                if (dbCM != null)
                {
                    dbCM.CountryCode = tmpCM.CountryCode;
                    dbCM.Identifier = tmpCM.Identifier;
                    dbCM.IsPreferred = tmpCM.IsPreferred;
                }
                else
                {
                    dbRecipient.ContactMethods.Add(tmpCM);
                }
            }

            //Only update this if it has changed.
            if (dbRecipient.LastModifiedBy.UserGUID != myRecipient.LastModifiedBy.UserGUID)
            {
                dbRecipient.LastModifiedBy = myRecipient.LastModifiedBy;
            }

            dbRecipient.LastModifiedOn = myRecipient.LastModifiedOn;
        }
    }

    context.SaveChanges();
}

public class User
    {
        [Key]
        public Guid UserGUID { get; set; }

        public string UserName { get; set; }

        public string FirstName { get; set; }

        public string LastName { get; set; }

        public string Email { get; set; }

        public bool IsSiteAdmin { get; set; }

        public bool IsActive { get; set; }

        public DateTime? CreatedOn { get; set; }

        public DateTime? LastLogin { get; set; }
    }

public class Recipient
    {
        [Key]
        public Guid RecipientGUID { get; set; }

        [Required(ErrorMessage = "Please enter a Recipient's First Name.")]
        public string FirstName { get; set; }

        [Required(ErrorMessage = "Please enter a Recipient's Last Name.")]
        public string LastName { get; set; }

        public string Company { get; set; }

        public UserGroup Owner { get; set; }

        public virtual ICollection<ContactMethod> ContactMethods { get; set; }

        public User CreatedBy { get; set; }

        public DateTime CreatedOn { get; set; }

        public User LastModifiedBy { get; set; }

        public DateTime LastModifiedOn { get; set; }

        public bool IsActive { get; set; }
    }

public class ContactMethod
    {
        [Key]
        [HiddenInput(DisplayValue = false)]
        public Guid ContactMethodGUID { get; set; }

        [ForeignKey("ContactMethodTypeGUID")]
        public virtual ContactMethodType Type { get; set; }

        public string CountryCode { get; set; }

        [Required]
        public string Identifier { get; set; }

        public bool IsPreferred { get; set; }

        [ForeignKey("RecipientGUID")]
        public virtual Recipient Owner { get; set; }
    }

context.Entry(myRecipient.LastModifiedBy).State = EntityState.Unchanged;