Well the story that you said is something i went through. Damn girl, the feelings that you are going through will drain you in such a way that you will lose yourself . First of all sweetheart you are head over heels in love with that guy and that is true love but but but the reality is- YOU CANNOT HAVE THAT GUY because he is in a relationship with someone for years.
He msgs you and stares at you because he is bored of his relationship, if he really liked you, he would have ended his relationship with his girl but he didn’t so he is just playing around because you are like a toy to him. Every word you mentioned i can relate to you because the exact situation has happened to me and my ending was pretty rough so from my experience i would suggest you to not waste your time and focus on yourself and move on because the relationship with your PT won’t have any future. You are young and beautiful,i bet you are good soul that’s why he loves talking to you and that means you can get much better than that guy. It will hurt for a while when you will move on but eventually you will and don’t forget to read this, it will help you out – http://www.sevenswag.com/6-truths-about-love-that-every-girl-should-know/