You and your spouse have had a huge fight. One of you has stormed out, and you know the relationship is over.
Can you change the locks on the home? Can your spouse change the locks on the home to keep you out?
If you are legally married, the short answer is "no, not without a court order or Separation Agreement granting you exclusive possession of the matrimonial home". It doesn't matter if the home is only in the name of one of the spouses.
This is one area, however, where the law is different for common-law spouses. In Ontario, common-law spouses do not have rights under Part II of the Family Law Act. A common-law spouse only has a right to the home if their name is on the title or the lease.
What if your afraid of your spouse, due to threats or violence? Emergency court orders can be obtained in extreme circumstances.