Why? Why do they still seek attention when they were the one who ended it with silent treatment?

Tha narc I was involved with in 2010 was an online emotional relationship. Luckily nothing else. However for some reason I got quite deeply involved. I have had to look deep within myself and have done alot of soul searching to get over this. He ended the relationship by giving me the silent treatment for no apparent reason. Prior to the silent treatment he had devalued me. 2011 was all about trying to get over this and moving forwards with my life and I have been NC with him. However his child and my children go to the same school and we live in a small town so sadly I have to see him. I have coped with this by basically keeping well out of his way but if I come face to face with him I will say a civil 'hello' or respond to any small talk with a yes or no and move out of his way as soon as I can. I unfriended him on FB and feel like I have generally got over him. I have seen his true unpleasant character and the more I have learnt about him the signs of narcissism are glaringly obvious!!! I have visited this site almost daily but funnily enough this week I haven't - maybe a sign I'm moving. However he does things to ensure he gets my attention. He comments all over friends facebook statuses, he parks outside my house at school pick up time and manouvres himself to be in my line of vision or walk near me. Today I had an experience this morning dropping the kids off at school where he seemed to manouvre himself to walk directly in front of me. I waited behind to be one of the last to leave and he waited by talking to the teacher,as soon as I headed off he did, I crossed the road - he crosssed the road. He turned and said hello and I said hi back and looked away. However he didn't talk to me but made sure all the way to his car that he was directly in front of me. Why why why? It just sets it all off again for me. This is not the first time he has done this either. He has done this loads, almost like he wants to talk to me but doesn't, or he waits in his car and watches until I am in my house. Or if I'm chatting to another parent in the street he will wait in his car and only go when I do. Of course he does all this discretly to not look obvious. Would he do this to intimidate me? Is it because he wants my attention? Does he want me to talk to him? I wish I didn't have to see him. By the way he's a cop and I think he's got a hero complex and most of the other parents think he's great!!! If only they knew!!