I can almost guarantee that is what the issue is. If your program is interrupted when you're shutting down the preferences don't get written and consequently, it corrupts your preferences. Once your preferences are corrupted, Photoshop resets everything to the defaults. Sometimes all of my preferences get wiped out and sometimes it's limited to certain type (i.e. styles, brushes, etc). It's a total PITB! Generally speaking, it's good to only load the styles, shapes, patterns and brushes you frequently use, since the more you have the more the system gets bogged down. You might want to try resetting them manually to see if that clear out your corrupted file.
http://www.margaretmarsh.com/tips/ph...prefs_info.htm