The thing you have to remember is he is her EX, she is with you not him, because he is an ex does not mean you sever all ties, some people remain really good friends, nothing wrong with that, I am in touch with my first ever girlfriend and she will allways be special to me, it just didn't work for us, I have been married 35 years, and my wife has no problem with me meeting my ex girlfriend for a drink and a chat, after all she is an ex, you must trust her, she wanted to go to his wedding I think it was a lovely gesture by him to have asked her and it shows she is a lovely person because she was happy, to see him happy, now forget it and move forward, good luck, new year, new start, Ray