If he has moved out, you have the right to change the locks. If you are afraid for your safety, you may have the right to get a domestic violence protective order against him. Domestic violence includes more than just direct physical abuse. Talk to Interact of Wake County (919-828-7440) if you want more information about domestic violence.
If you have any question about whether a court would believe he has moved out or not, talk to a local attorney who can go into more detail about the specifics of your situation.
Yes, you can change the locks.
You need immediate legal representation. This answer is offered for informational purposes only. It is not offered as, and does not constitute, legal advice. Laws vary widely from state to state.
You should rely only on the advice given to you during a personal consultation by a local attorney who is thoroughly familiar with state laws and the area of practice in which your concern lies.
There is a big difference between moving out and "leaving for about a week".
If all of his personal effects are in the house, than I would question whether he moves out with the intent to remain out permanently. There is no law that prevents you from changing the locks, but if you own the house jointly, there is no law that would prevent him from breaking in to get back into his own house either. (I'm assuming there is no separation agreement).
I recommend that you talk to an attorney about this. Good luck.
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