One of my Wiccan teachers told me I was empathic. I'd always had a sneaking suspicion I could feel other people's emotions, but of course I had no proof. And I'd always thought the idea of being psychic was cool, but I didn't think I was since I didn't have experiences like you see on TV or whatever. I got into astrology when I was 12, and soon started trying to guess people's signs. I've actually gotten good at it. I'm definitely correct more often than random guesses would be. The signs have different "vibes," much like I see people on here saying about types.
Being empathic has a unique set of strengths and challenges. Especially for an INTP (inferior Fe, and shadow Fi). I get all this emotional energy from people, and since I don't really recognize it well in myself, I both get confused about what emotions are mine and what are someone else's, and I project things onto people which aren't necessarily there. And I'll feel what someone is feeling, but not have the slightest idea why or what I should say to them to make them feel better. So I just avoid emotional people. The projection works like this: say one of my superiors at work talks to me about a mistake I've made. I can sense he's feeling stressed because it's busy, and my inferior Fe wonders if I am part of the reason he's stressed. My Si recalls past experiences where bosses have been unreasonable and yelled at me, and my emotions about those situations bubble up and confuse themselves with what I'm feeling from him, and so the feeling is magnified, and I project onto him that he must be angry at me. When in reality he's just stressed because it's busy, and the situation isn't anything personal about me at all. Once I consciously know that, it happens a lot less. My hypersensitivity is connected to Si and Fe rather than Fi, and it's magnified with being empathic. When I can wrap my mind around something, my feelings usually comply.
When I feel emotion from people it's like feeling it in myself. I can't readily put a label on it- it's just a jumbled up mass of intuitive perception and a physical feeling. Unless there's a clear reason for it, like if I'm watching someone experience something traumatic. I feel it acutely and want to cry with them. I like to think I'm so tough, but I feel these things against my will, like my psyche goes into theirs. The first time I cried at a song I was super embarrassed and secretly hated myself. But it was really therapeutic, because I felt a connection to people. I can identify with Fi to some extent this way, with the difference that I don't seek emotional experiences out. I personally am not all that emotional, so strong emotions in other people seem way more dramatic and traumatic than they are- because if I was being that emotional, it would be over something really awful. My emotions have multiple layers, and it takes me a lot of introspection and analysis just to label some of them, and then come up with the reasons why. I'm actually very good at analyzing people psychologically with what I intuitively feel from them.
In one empathic incident I had recently I was hanging out with the guy I'm seeing. He had said he'd been feeling depressed lately. We were lying on my bed with my head on his chest near his heart, and trying to cheer him up. I had started to feel depressed to and didn't know it. He said he had to go and couldn't spend the night. When he said it I felt really sad, like I wanted to cry. Then something in my mind said, "Hey, this is not normal. You've never felt like crying in this kind of situation before- what's up?" I figured out I was feeling his emotion, internalizing it, and since I had nothing to feel sad or depressed about, it grabbed onto the only thing available which was that I would rather he stayed; and produced an overreaction from confusing his emotions with mine. (I told him, and he said he'd stay after all.) It was because I'd been around him for awhile and my head and heart were near his heart. I've had a couple of other instances where I've been lying like this with someone and my heart felt suffocated, and I found it physically hard to breathe. That kind of freaked me out.
It makes social interaction difficult. Since other people are more emotional than I am, and I don't always know why, I just went around feeling overwhelmed by people's energy and thinking people were unpredictable (and so avoided them). Once I found out I am empathic, and learned how to use psychic shields, my life became way easier. Which is evidence that it is true. And like I say, it's my reality, so I kind of have to believe it and act accordingly, because doing so makes things easier.
I can use it for healing. I have a talent for balancing energy, particularly feminine and masculine; so sexual healing and energy work are natural for me. I do it automatically. I can intuitively sense what people are like sexually, and how that relates to their emotional and psychological needs, and give it to them. I don't really think about it most of the time, and it's not my motivation for having sex with someone. I just attract people who need what I have to give, and who have what I need, and we heal each other. I see it as a spiritual thing. The divinity in me connects with the divinity in you, namaste, etc.
The rational explanation: everything is energy. Electricity goes through living things. The heart has a magnetic field which spans several feet. Intuition is all the sensory information we receive combined, plus what it all tells us. Our consciousness couldn't possibly process it all, so it's processed in our unconscious mind, which sends its conclusions and relevant bits of data to our conscious mind. Psychic ability is simply highly developed intuition (Ne+Ni), and anyone can develop these functions, so theoretically anyone can develop psychic ability. (And opening and balancing the third eye helps.)
Sorry for this rambling wall of text; notice that when I'm talking about something purely rational I'm pretty organized, but when I'm talking about subjective things it tends to be a jumbled up mess.