I'm stuck

My ex was emotionally abusive, that's why I ended us. After I broke up with him he's been trying to get back with me, says he's changed, then wants to meet for sex. I try and try to fight my feelings for him, because he was the only one I wanted to marry. But I can't, I keep giving him chances. Now the reason I don't just delete him is because he has a video of me sucking him off and many nudes he screen shot of me. Last time I went to end it he sent the video of me, when I asked why he said "idk".