I've seen my ex a few times when I've had to travel to London to see family. Usually only at the odd funeral or wedding. I would not bother to talk to him, and would pass him without any remarks or greeting at all. At Euston train station a couple of years back, he came over to me with no. 3 or 4 in tow, and proceeded to tell me that I looked tired and had put on weight, total crap, I've been a size 10 for over 30 years. I would have tried to be reasonable, but he left me, for one of his floozies, and then became bitter when he couldn't make a go if it with any of them. When I refused to take him back and I met my wonderful DH through work, he became nasty and I had to take out a restraining order. There is far too much animosity on his side for us to ever even be civil to each other.