Hi guys just looking for some advice. I recently found out that one of my close friends is dating my ex. We split around 4.5 years ago after a very toxic relationship, she is very aware of everything he put me through. She has recently come out of a long term relationship and I supported her throughout her break up. I had my suspicions about her dating my ex and she started posting memes on facebook about me so I asked her directly and she explained it was about someone she was dating. I asked who and she would not tell me. Over the passed few weeks she has stopped messaging, calling and liking anything I post on facebook where as we would speak everyday. When I had confirmation that she was dating my ex I messaged her saying that I was glad she put a male before our friendship and felt it was ok to betray me. She completely denied it and said she had no clue what I was on about but then did admit it and said well we are happy so that's all that matters, she then switched her Snapchat location on so I could see she was at his house. I did then fly off the handle at her and later blocked them both on social media. I really dont care that they are together but I am hurt that she could betray me like that then completely deny it when I've supported her after her split and offered to help with money etc. Apparently I am jealous and bitter but im not. Im engaged, own a home and have a beautiful baby I just can't understand why a friend would do this especially after knowing how awful he was to me.. Advice please, have I over reacted?