So my most recent attempt with this girl went downhill since she tells me she has a boyfriend now. I was pretty sure she was interested because we would flirt all the time and talk about sex and kissing and stuff and I even tried to get her to chill with me but she says i never made a move on her. I felt like I clearly showed my interest but maybe this has been my problem all along. How do you make sure for a fact that she knows that you're interested?