Oftentimes the WhatsApp app crashes because a recent update to the software was corrupted. Basically, there was a corrupted or damaged file that was downloaded and installed. To remedy this, you'll need to re-run the executable to have the update installed correctly. After the update, go ahead and restart your computer to see if things are better. Alternately, you can open WhatsApp and go into the advanced options. From there, click the Reset button. Once that's done, close the app, open it back up, and see if it stops crashing. In extreme cases, you may need to uninstall the entire app and then reinstall it again. If this is the case, something has gone wrong with the internals. Let me know how you make out.