Even though empathy is something that everyone strives for and is taught at a very early age, empathy used to the extreme can allow someone to erase their own needs, emotions and frustrations for the sake of another person.
It is so easy to forget about your need when you focus so hard at understanding someone else’s need and want. Since you are suffering so much, it becomes very easy to relate to someone else’s pain and frustration, and you almost project it as if it’s your own.