Empathy

em·pa·thy noun \ˈem-pə-thē\
: the feeling that you understand and share another person’s experiences and emotions : the ability to share someone else’s feelings

Full Definition of EMPATHY

1
: the imaginative projection of a subjective state into an object so that the object appears to be infused with it
2
: the action of understanding, being aware of, being sensitive to, and vicariously experiencing the feelings, thoughts, and experience of another of either the past or present without having the feelings, thoughts, and experience fully communicated in an objectively explicit manner; also : the capacity for this.

(Ssource)

Sympathy

sym·pa·thy noun \ˈsim-pə-thē\
: the feeling that you care about and are sorry about someone else’s trouble, grief, misfortune, etc. : a sympathetic feeling

: a feeling of support for something

: a state in which different people share the same interests, opinions, goals, etc.
plural sym·pa·thies

Full Definition of SYMPATHY

1
a : an affinity, association, or relationship between persons or things wherein whatever affects one similarly affects the other
b : mutual or parallel susceptibility or a condition brought about by it
c : unity or harmony in action or effect
2
a : inclination to think or feel alike : emotional or intellectual accord
b : feeling of loyalty : tendency to favor or support
3
a : the act or capacity of entering into or sharing the feelings or interests of another
b : the feeling or mental state brought about by such sensitivity
4
: the correlation existing between bodies capable of communicating their vibrational energy to one another through some medium.

(source)

I think empathy and sympathy are often confused for one another. Empathetic people understand others very well; consequently they are often the least sympathetic BECAUSE they understand others so well.

Food for thought!