I've got a hole in my heart that doesn't belong to me.

Is there a word for this? I take on people's emotions and absorb them. Whether it be my friends, someone I've met, or a character in a book or movie (be it fiction or non-fiction). . . I simply feel too much for them. 

I've got holes in my heart that I don't deserve.

I've got wounds that weren't directed at me. 

This goes beyond sympathy or empathy. . . things stick with me and while I don't think about them, deep down I do remember them. And every time someone or something new stabs at me, it's all that much worse.

Maybe its a mix of depression and compassion. How the hell does that work? I've tried to look this up, but what do you look under? 'Painfully Compassionate'?? Compassion is supposed to make you happy too. 

I'm writing this as I google. I'm an internet-savvy hypochondriac. And the closest thing I have found is 'compassion fatigue' but that's still not quite it. 

I can't find anything that fits. If you know what I'm talking about, please comment! It would help.