What are my tenant rights in tennessee?

I have recently moved from florida to tennessee, I have a little apartment in oak ridge. I have a full time job and a semi- disabled partner who would be unable to defend himself in case of emergency and is very juggernaut about keeping the door locked at all times. Well over the past two months there have been several instances where we have come home anf found the door unlocked, and odd things have happened. Like important personal files on my computer being left open, and the channels on my television being changed to shows that me and my partner do not watch. The most recent occurence has been when he was home alone and in the shower, someone entered our apartment, and then ran like a bat out of hell when they noticed he was home. He saw the maintanance man leaving so fast he almost missed him. The office gave us some bs excuses about how he came in to check and apartments plumbing, to a unit 302, which we checked and that unit isnt even in the same building. He is now very fearful of someone coming in why we arent herem and he has not slept in two days. Literally, he is so scared that when i walk back in from having a cigarette he jumps, even though he knows im am out there. I would like to knwo what we should do about this situation?... Is there any way that this would be seen as a breach of contract by the court system?.. Im willing to do what it takes to find us a more suitable home.