Empty means:
* Having nothing inside: A glass that is empty contains no liquid.
* Lacking content or substance: An empty promise is one that is not likely to be kept.
* Without people or activity: An empty street has no cars or pedestrians.
* Feeling a lack of emotion: She felt empty after the breakup.
Empathy is a completely different word. It means:
* The ability to understand and share the feelings of another person.
Let me know if you had something else in mind!