Welcome to the board!!.
This is a great ?. and this just happened to me this week as well. my ex lives/lived (can't tell at this moment-I think he went back to his ex-wife) in the same complex as I do. He past me at the mail box, so I just waved. I don't want to be immature about it all. He ignored me, then proceeded to call and quickly hang up before I could answer. So I don't think that is the best way to handle bumping into an ex..
For your situation, treat him like you would any other individual. At least smile, just don't make eye contact too long so he doesn't think he has to come over and say hello. See I smile at just about anyone that passes me, so this wouldn't be anything special. Don't ignore him anymore, or I think you will be considered the stalker ex..
The best thing to do is to say hello and move on. If you really want to let him know that his behavior was not the most mature, you can say that you never heard back from him so you assumed that he was no longer interested in dating (online dating with Match.com) you and all he had to do was say so, but you thought you'd say hello...
If a guy did something totally crappy like not ever call me anymore with no explanation I would never speak to him again. He would not deserve a hello from me. In fact last year, that happened to me. I saw an ex in the library. He was walking with a friend. He smiled as he was walking toward me and I guess he was intending on talking to me but I just had a straight face and walked right past him..
I dont like faking nice. I hate that. My message is that you cannot treat me like crap and expect me to be friendly to you. And telling him he is a jerk etc is a waste of time bec they already know they acted wrongly. I do not need to tell them something they already know. I am not uncivil. I just will not talk to them (him) bec life is short and I don't need to waste anymore time on someone who was ok with treating me badly. ..
I would definitely be nice as piewith the intention of course of making him feel like the heel he is. It might not work but it would make me feel better. And no, of course nothing would be mentioned about his bad behaviorI'd pretend it never happened and he was just someone I knew from around the neighborhood. .
And what's up with YOU worrying about how you come across to HIM? He's a putz, his opinion isn't worth a dime!!!.