I keep 'favoriting' profiles just by sending them a message when I did not click on the 'favorite' heart, how do I stop this? I can go in a 'block' them by doing a generic search and clicking on the 'x' in the upper right of their profile, but they still show favorite when I do a 'who's online' search.

The heart just tells them that you like them, you use to be able to click the heart again to remove it but not any more. Once you click it then it stays.
Clicking the X only removes the profile from your search results, but even that is not forever. Profiles will pop back up, it seems random though so it is probably another mess up that the programmers here are unable to fix.
To actually block them it looks like you can only do it through the mail system. So a message has to be to them or from them. Then under the message box it gives you the option to block them, I do not see it on the profile anymore.

Thanks