Is it Customary Under Certain Circumstances to Provide Personal Information on one's Academic Website?
In US academia, I have never felt there is any expectation that an academic website should contain any personal or family information, such as marital status.

Some people choose to post personal information; this is their choice and (within reason) considered to be fine. Some people choose not to; that is their choice and considered to be fine. 

You won't find my marital status on my professional web page, as I happen to feel that it's irrelevant to anyone looking for professional information about me. Nobody has ever even suggested to me that I should change that.