It doesn't reinstall the game, what it does is reinstall the latest version of the launcher and setup files. It will recognise the files you have already downloaded.
Did you try running the launcher in safe mode? Same question to the other posters in the thread.
Additionally are any of you using SWTOR Unleashed? This can cause patching issues so please remove this if you are.
Also what Anti-Virus are you using?
I'm sorry this use didn't read Unleashed instructions and made you lose your time.