Relationships are shown twice
As per the code the select list loads all relationship types of corresponding Contact's contact Type. So for instance [Employee of (Individual type), Employer of (Organization Type)] Relationship Type(RT), if you are going to add relationship for Individual Contact A then on you will only see 'Employee of' (not 'Employer of') RT. 

In your case "other projector contributor' and 'other project contributor is' are both related to same contact type thats why you are able to see both on select list.