What is the ruling on a wife disposing of her husband's money by depositing it into her private account or buying gold without his explicit permission and repeating such actions, and is the husband in the right in what he believes?

You are right to object to your wife depositing money into her account without your permission. It is forbidden for her to dispose of your money without your consent, unless you fall short in providing for her, in which case she may take what is reasonable. As for what she previously agreed to, she is excused. We advise you both to abandon disputes, for Satan is keen on destroying your relationship. So, the wife should repent and abandon these actions, and you should be patient and counsel women, as the Prophet, peace and blessings be upon him, said: "Treat women kindly, for woman was created from a rib, and the most crooked part of the rib is its upper part. If you try to straighten it, you will break it, and if you leave it, it will remain crooked. So, treat women kindly."