Module not found: Can't resolve 'react/lib/React'

Your case it is clearly react and react-dom packages incompatibility. Make sure that your react and react-dom packages have the same version to avoid incompatibility.

package.json now:

...

"react": "^16.2.0",
"react-dom": "^15.6.2", 

...

package.json with compatible react-dom and react packages:

...

"react": "^16.2.0",
"react-dom": "^16.2.0", 

...

Since react-v0.14-beta-1 react and react-dom are separate libraries and you are supposed to use the same version.

For now, please use the same version of react and react-dom in your apps to avoid versioning problems — but we plan to remove this requirement later. (This release includes the old methods in the react package with a deprecation warning, but they’ll be removed completely in 0.15.).