Latest version of ST Crashes when opening a Repo

Not sure why your "Affects Verion/s" menu does not have the version of Source Tree that Source Tree itself advertises (1.8.1.0) so I selected the closest one.

After updating I had one day of normal use. This morning, after re-launching SourceTree (closed it last night), I am unable to open my primary repository. I've manually verified that the repo directory and its associated .git folder both exist. I can open other repositories in the same D:/Repos directory, but not this one.

I am able to launch Git Bash in this repo and run Git commands such as "git status" or "git checkout ." It appears ST simply crashes.

Probably unrelated but other behavior I noticed: Since I updated to the latest version using ST's "Help > Check For Updates" I have been unable to keep subrepositories opened. If the window loses and then regains focus, my opened subrepos simply disappear, and the bookmarks are considered "invalid."