Can My Roommate Have Access to My Room?

Hi I live in Florida and I have a roommate who oversees the apartment for the Landlord (handles any repairs needed with Landlord's approval, send rental payments to the Landlord and is responsible to find a tenant for a vacant room). I was told that I need to give a copy of my room key to the Landlord. I don't have a problem with that, however, since my roommate oversees the apartment, I am concerned that my Landlord would allow her to hold the key and she would have access to my room which would defeat the purpose of me changing the locks in the first place. I would ask her for the Landlord's address in order to mail the key to the Landlord directly, but I have a feeling that she will see to it that the Landlord gets it (she's protective over giving out information such as phone numbers and addresses). Since she is not the Landlord, does my roommate have the legal right to have access to my room? Also, don't I have the right to have the contact information for the Landlord for business purposes? Any suggestions would be greatly appreciated. Thanks!