What is the difference between sympathy and empathy?

I was never quite sure of the difference between sympathy and empathy and just looked up the meanings.
Several places that I checked treated the words almost interchangeably which would explain why so many people use the words incorrectly.
I did however find the following descriptions which satisfied me.
Sympathy and empathy are both acts of feeling, but with sympathy you feel for the person; you’re sorry for them or pity them, but you don’t feel their pain.
Empathy can best be described as feeling with the person.
Notice the distinction between “for” and “with”.
If you’ve ever had a headache and somebody tells you that they have a headache then you can imagine what they feel and sympathize with them.
Even if you’ve never had a headache though, you might be sitting next to somebody when suddenly your head hurts and that’s because you’re an empath.
You’re feeling their pain, so sympathy and empathy are very very different.
After fully understanding the above I wondered if it would be good to be an empath and decided that it would most likely be horrible.
But maybe it has its upside?
What do you think?
As I understand it, everyone is born an Empath because we all have the physical equipment necessary to pick up on what other people are feeling.
But, for most people, this ability will slowly fade away from lack of use.
The following is what I believe to be a basic categorization of Empaths:
So in answer to the question, "Would it be horrible to be an empath?", the answer would seem to be that you’re already an empath and that was is important is to know how to control the ability.
A postive thing might be, that I reckon that it would be almost impossible to lie to a functional or trained empath as they would pick up on it immediately.
They might not be able to discern why you were lying but they’d almost certanly feel that something was not as it should be.
I now feel that something that happened to me recently for which I had no explanation, now how one.
I woke up in the morning after a restless night’s sleep feeling depressed and down.
But everything in my life was going well so I couldn’t understand the feeling.
A little later in the same day however I got a message from a close friend telling me about a catastrophic event that had just occured and he emphasized how depressed he was.
I instantly realised that I woke up feeling HIS pain.
Right now, I’m going to surf for information on empaths.
Because empaths are very likely to have telepathic abilities the following abilities are also more than likely present.
Empaths generally find that they easily adopt, or are influenced by philosophies of another even when they are in opposition to their original philosophy
Being physically near or distant to the source does not normally affect an empath’s sensitivity.
Below, are some quotes that I found which might perhaps provide some insight into the positive side of being an empath.
Anyone who has experienced a certain amount of loss in their life has empathy for those who have experienced loss.
Anderson Cooper
When you start to develop your powers of empathy and imagination, the whole world opens up to you.
Susan Sarandon
If your emotional abilities aren’t in hand, if you don’t have self-awareness, if you are not able to manage your distressing emotions, if you can’t have empathy and have effective relationships, then no matter how smart you are, you are not going to get very far.
Daniel Goleman
Learning is a result of listening, which in turn leads to even better listening and attentiveness to the other person. In other words, to learn from the child, we must have empathy, and empathy grows as we learn.
Alice Miller
The discoveries of how we can grow and the insights we need to have really come from the inside out. To have genuine empathy, not as a make-nice tool but as an understanding, is essential to the next step.
Patricia Sun
The great gift of human beings is that we have the power of empathy.
Meryl Streep
There are many respects in which America, if it can bring itself to act with the magnanimity and the empathy appropriate to its size and power, can be an intelligent example to the world.
J. William Fulbright
True contentment comes with empathy.
Tim Finn
We need somebody who’s got the heart, the empathy, to recognize what it’s like to be a young teenage mom, the empathy to understand what it’s like to be poor or African-American or gay or disabled or old – and that’s the criterion by which I’ll be selecting my judges.
Barack Obama
What Mr. Obama wants in a nominee isn’t really “empathy” and “understanding.” He wants a liberal, activist Supreme Court justice.
Karl Rove
I read some time ago that according to traditional science that empathy is genetic, inherent in our DNA, and is passed from one generation to the next, and it surprised me at the time because I’d always thought that empathy was most likely developed by mediation and similar practices.
In addition to being able to sense the feelings of others around them developed empaths apparently know the thoughts of others too.
If we then add to the above that many empaths are also very good at reading body language, including eye movements, it’s hard to imagine that they don’t suffer from informational overload, and although it would be interesting to experience what an empath experiences for a short time, I’m pretty sure that I wouldn’t want to be one.