Why does it feel so good but hurt so bad

My mind keeps saying, run as fast as you can. I say i'm done but then you pull me back.
Oh oh oh, I swear you're giving me a heart attack, Troublemaker.
It's like you're always there in the corners of my mind. I see a silhouette every time I close my eyes. There must be poison in those finger tips of yours, cause I keep comin' back again for more.