Safari reloads excessively, with unusual effects
Starting today, Safari has refused to let me log into different websites. For some, right at the point that it appears to log in successfully, it suddenly reloads and goes back to the log in screen. For others, where I have previously clicked "keep me logged in" or an equivalent checkbox, it tries for a few minutes, and then comes up with
Safari can't display this webpage
Safari has repeatedly encountered an error while trying to display
"https://www.facebook.com".
It also affects some websites I don't have to log into.
I have closed safari and re-opened it. The problem is still there. I've reset safari. That didn't help. I followed the instructions in this article, but safari was still acting up, so I put everything back. I guessed that the problem was either safari or my computer either overheating (a frequent problem it has, which has been slowly getting worse as it ages) or failing to connect to the network. It was easiest to try another browser, so I did that first. Lo and behold, Chrome works, so I know the trouble is with Safari, not with my computer or its internet connection. I'm just running out of ideas of how to fix it.
The weird thing is, a few pages constantly reload until they come up with an error message, some only reload when I try to log in, and some are perfectly fine. I could view www.xkcd.com with no problems, but what-if.xkcd.com refused to load. Gmail only reloads (which causes logging out, as though the browser had been restarted rather than the page refreshed) right when the progress bar loading the inbox reaches 100%, before the actual messages appear. Pokefarm reloaded with the effect of causing me to be logged out every couple of pages that would load, until I checked the "automatically log me in" box one time when I logged back in, and now it only reloads the page every once in a while. Facebook (which I've left logged in near-permanently on my computer) refuses to load. My student account logs in, sometimes long enough to click the email link, then almost immediately goes to the "session has expired" link on both tabs. I'm not finding any particular pattern except that each website is consistent in how it acts. I'm really getting frustrated
Ideas, anyone?
MacBook Pro, Mac OS X (10.6.8), Safari Version 5.1.7 (6534.57.2)