My columns are messed up

A plugin may be responsible for this; try disabling plugins.

I will try that, thanks!

I did not change anything!

you posted a post (that is a change as well)

the same sidebar problem shows in the single post view of the latest post;

also reflected in the validation report: https://validator.w3.org/check?uri=http%3A%2F%2Fwww.paulinebjones.com%2FBlogWP%2Ffriday-vid-and-some-alien-links&charset=%28detect+automatically%29&doctype=Inline&group=0

Line 49, Column 427: end tag for “div” omitted, but OMITTAG NO was specified

using the html setting of the post editor, double check the content of that post for unmatched divs;
particular this line:
<p><div><a href="https://www.paulinebjones.com/BlogWP/wp-content/uploads/2012/08/anabananazombies2.png"><img class="aligncenter wp-image-540" title="AnaBanana Bath & Body Treats" src="https://www.paulinebjones.com/BlogWP/wp-content/uploads/2012/08/anabananazombies2-300x136.png" alt="pauline baird jones, author, writer, romantic suspense author, science fiction romance author, steampunk" width="180" height="82" /></a></p>

oh wow, that did it, thank you! I wonder how the div code got in there? Thank you so much! I think I’m back!