It sounds like she has OCD for cleaning for sure. OCD is tied to anxiety, so she probably has other anxiety problems as well, which is clear from her apologizing over and over again. Also texting over and over again about things goes with both her OCD and anxiety. Carrying her clothes everywhere could have something to do with her anxiety or also some trauma she's experienced. You said she had someone in her family threatening to kill her or other people? That could be she's been through some abuse or seen her family go through it. And maybe carrying her clothes is an OCD thing like she's afraid to lose her home.

Otherwise, no one can diagnose her here. She has depression by her own admission. Depression can cause you to isolate yourself. That could be part of that.

The thing with the knife sounds like a panic response. Ruminating thoughts on your text probably built up in her and when you confronted her she panicked. Not really a healthy response, but if she's shown no other signs of aggression it could have just been situational. But, you say you don't feel safe, so that's not a good feeling in your home.

If you feel unsafe there is only the lease keeping you there. It could be you just need to cut your losses and move on.