Empathy but no sympathy

My whole life, the more someone gets to know me, the more they slowly start to notice that i dont care "about" others. I want to say i can care "for" or "about" others in the sense that if they interest me for any reason, that interest i have in them translates into me caring about their fate. Generally i dont mind if anyone dies unless i have a particular obsession with them that invlolves or requires them to be alive, i literally dont care if they die.

This shocks the hell out of people but i am honestly oblivious to why, other than the fact that i generally belive most people lie to themselves about morality, selflessness(which i belive is impossible, and a mosunderstood paradox). Yet i recognized that i do not feel mercy, or sympathy. Its extremely rare, and i love it when it happens, but i have felt compassion before, but never more than a few moments at a time, and after a day or so, its long gone.

This has given me allot of trouble in romantic realationships, phscycologically im very preceptive, and i have no idea why, but people trust me, and it dosent take me long to find someones deepest fears, or most frantic personal issues, and if its a woman, the next step is to get them to fall absolutely 100% in love with me, make their most sensitive dreams come true and bring them to the absolute pinicacle of happiness. Then i absolutely tear their world apart, and leave their mind in complete shandals. It helps if they allow me to physically hurt them, however i still need to rip them apart emotionally. I know that i have truly hurt women in the past two years, their come a point when you realize that its not always a game, i mean it really isn't. When you cross a womans line, they can't report you to the police, if they love you or are a masochist with a long history. Everything a woman has told me they cant handle, ive done it. Ice, freezing water, fear of moths, spiders, forced vomiting, they went beyond a very clearly established consent, and i was never forgiven for any of them, yet the fact that they didnt report me and somehow still love me, but yet broke ties with me completely just tells me that they veiw me as a victim just as much as them, they no longer trust me, but want to protect me, keep me out of trouble. To me it shows unconditional love, and i that truly fascinates me because ive never seen it before.