An example: Six or seven years ago, I was sitting in a Starbucks with a girl I had had a crush on in high school. She had tracked me down hoping I was still interested in her, which I thought was awesome. About half an hour after we had arrived, this other guy that was interested in her shows up. He moves a chair over and places it with the back toward me, which was really awkward because of how close to her I was sitting. After a few minutes she points out that she's on a date and would prefer to talk to this guy later. He turns around briefly, says "oh, sorry, I didn't see you there." He turns back to her and asks "is this that gay friend you were telling me about?" He then suggests that her and I say goodbye while he gets a coffee and then that her and him should sit and talk more. She suggests that they meet on another day, he gives up and leaves.
I mostly found him to be a minor irritation, but he was clearly trying to provoke me. Questioning my sexuality is pretty high on my list of "things I don't give a shit about," but that isn't true of a lot of men. After he left I commented "well, that was odd." and got on with my evening. I called her two or three days later to set up another date, and she was with this guy at the time. After finding out it was me on the phone, I distinctly heard him say "hang up or I'm going to kill that motherfucker." So, I said I'd call her back later. After I got off the phone I was thinking this guy definitely made an ass out of himself, and he'd go away shortly if I ignored him. What happened instead is that they were together for three years and had a kid together. At the time I was thinking I screwed up somehow, but now I realize that she screwed up by not telling that guy to fuck off.
She didn't "screw up", she made a choice that was not you. You may think this was a bad choice but it was hers to make. If she was still interested in you she would have kept seeing you and not started seeing someone else, it's as simple as that.
One thing that strikes me is you seem to talk about women as though they can be manipulated and tweaked into making relationship choices, as though it's you versus other guys and the women are the chess pieces and you are trying to decide what your next move and counter move with the other guys should be.
You can't actually tweak a situation in such a way that it produces your desired outcome. Women make their own decisions.