I kind of have the same issue but only on my iPhone or iPad. The "keep me logged in" checkbox is checked but after I login in works fine for that day but the next day I am always logged out but only on my iPad or iPhone. I have deleted cookies and ALL website data multiple times but it still happens over night every night unless I use a different browser. It only happens using Safari on the iPhone and iPad but not on my iMac. I have given up on it and just log back in everyday. I have checked settings but nothing has helped. And it didn't just start recently. It has been happening for quite a while. And it only happens here, DBSTalk and Facebook. All other websites keep me logged in even in Safari on iPad and iPhone.