Will you smile and greeth your EX ?

Hmm, yeah. Probably. Past is past. Since i'm a guest and so do my ex, just smile and greet as a guest. Unless if i still have feelings for my ex, then it would be very weird.

It is ethical to smile and greet your ex. Than, avoiding him/her. It may give a bad reputation to you. He may think that you are still in pain. If I am to ask, I will greet him if he greeted me, be ethical in that event. I will be proud of myself when he sees me. What made me now after we broke up. Reconciliation is the best thing to do. It will give inner peace of mind and acceptance.

I would not go out of my way to make contact with my ex. After-all, if that person was important, they would still be in my life in some fashion. But, if I was "forced" into contact, I would smile nicely and be on my very best behaviour.

I will not make the first move but if ever faced with such a situation, I will be civil enough to acknowledge my ex and make polite conversation. I think the best way to handle situations like this is to show that you have moved on with your life and you're happy. To show that you're still affected might raise suspicions that you still have some old feelings and bitter memories.