Welcome to Just Answer
I am a Solicitor and will assist you.
I am sorry to hear about the difficulties that you are experiencing with you wife.
In relation to the Matrimonial Home - you are entitled to legally live at that property by virtue of being a joint tenant and also because it is the matrimonial home.
If your wife did change the locks - then your would be able to obtain new locks to gain entry - you would also have to give your wife a key.
There are a few ways of excluding people from a property where they are legally entitled to reside.
The police could be called if there was an incident. The police can ask someone to leave on a temporary basis usually overnight to prevent a breach of peace. If the police make a charge - then they can put bail conditions in place preventing someone from going to the property for a period of time.
Please note that your wife could also seek to obtain an occupation order - these orders usually restrict someone from returning for say 6 months. Judges are often reluctant to make such orders unless absolutely required as they do not like making people homeless.
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