Try turning off the graphics card acceleration. This is found in Preferences->Performance
Please follow the below steps and see if that helps.
> Launch Lightroom
> Click on Edit > Preferences(in Windows)
Lightroom > Preferences(in Mac)
> Click on Performance tab
> Uncheck the option use graphics processor
> Click on Ok
> Quit Lightroom
> Restart your machine and check for the issue.
If you are no longer able to launch Lightroom, please follow the steps provided in the below link.
Also, please mention which operating system are you using?
Please post the error log.