I need help

I'm in a happy relationship, but my ex wants me back. I relationship was abusive and I loved him, still do a lil bit. He just texted me telling me how he loves me and misses me and wants me back, and I'm crying because he never told me that before. I'm not gonna take him back, but after telling him how he mad me feel he said he's going to kill himself. Why did I have to meet him... why do I still care for him.