If you can't get over the fact that your ex is walking around looking like he does not care a bit about you and You need to come out of your shell and work on your personality. Discuss your dating problems on our forum.
She eventually started dating a new guy and I was fine with it. It hurt and I miss her being in my life, but I can't have someone trying to make my life harder to deal with. Like your ex-boyfriend said in your situation, “I have too much on my plate.” tiny seed of a thought about their ex-boyfriend seeing it and being jealous.
Before you read any further, I want to make one thing clear. You see, jealousy isn't something that you can shove in your ex's face. This way her own mind does half the work for you. And if not, all you have to do is put up an innocuous picture of you and your date doing something fun in public, and I guarantee she'll