I’m having the same problem you had. My site is using a huge amount of physical memory, and images are not loading properly.
I’m currently using the WP Super Cache plugin, but it does not appear to be helping.
I have upgraded to wordpress 3.5 and updated all of my plugins, but to no avail. I’m not very comfortable messing with my htaccess file, but I ‘m not sure what else to do. Was hoping you might have some other ideas on how I can solve this issue.