Well, if you click on preferences in the bar up top, you'll see this:
The direct link to your profile is: http://www.realjock.com/meninlove
Allow everyone to view my profile
Allow only members who are signed in to the RealJock site to view my profile
Temporarily hide my profile from everyone, including other RealJock members (Note: your profile will not show up in searches and you will not be able to instant message with other RealJock members)
...sorry the boxes to check right after each option description didn't paste.
Some people do it when they're away or want to take a break. Some do it to troll; no emails when they're hidden.