When I was in grade 6, I had this friend who was an ENTP -- we got along awesomely but I can recall feeling pangs of jealousy if he didnt want to spend time with me and decided to spend time with other friends instead. Of course among all his friends I was still his best one because we were the only ones who did lots of N stuff together.
I also recall this one time 2 years ago I became interested in an INFx woman, she was generally a poor-me type and I came to visit her one day and we walked to the park and sat on the swingsets and talked about various things, I was in good spirits at the time and wanted to listen to her and help her because she was interesting -- we went back to her place and talked about various things including god and came to somewhat a rather heated disagreement although I still tried to learn her perspective and still liked her. I tried to get her to go on a date with me and she stated she was on her way soon but she ended up standing me up and when I called she said something like she was too shy to come, I was really disappointed to the point of being hurt. I tried to arrange meetups with her twice and she seemed to have some kind of excuse and because I felt like something was wrong with me when she would not come with me I eventually dropped her cold. I asked her why she did not want to ever come to any event I set up, and she could be as brutally honest as possible and she said she didnt know -- so with grim finality I told her that it was fine, I was never going to contact her again -- she called once for me months later but i completely cut her out of my life and would not return her call. This is how I know I might be clingy when the situation comes up, because I attach too much emotional value to the person who I'm interested in. I generally avoid any situation which may become a romantic one although part of me wants it, because I don't want to be 1) Played for a chump, or 2) Rejected at some point -- because rejection hurts when you pin your hopes on your plans working out.