Hi there,
Sorry to hear about your experience. We'll be happy to help. Would you mind sharing version of the OS & Adobe Illustrator? Please try resetting the preferences of the app by following this help article & let us know how it goes.
**Please note that resetting preferences will remove all the custom settings and Illustrator will launch with default settings. You can also take a backup of the folders in case you want to. Location is mentioned in the article.
Hope it helps.
Regards,
Ashutosh