It keep being an issue, today Resharper collapsed again after a major refactoring and a get latest version.
Highlighting is permanently disabeld, so that can't be the issue. I'm using Find Usages a lot and did a couple of debug runs to make sure everything was still in working order.
A couple of issues have been created, 974* all OutOfMemoryExceptions.
Hope you can do something to fix this soon. It's becoming more and more depressing...