Thanks for all the thoughts on this.
My ex was mentally and emotionally abusive. Examples of this would be: If we were in public, he would do or say something inflamatory, to get a response, something usually hurtful, when I would try to defend myself he would retort with something to make me feel small or stupid. My DD started to have a weight problem, so I asked that he limit treats to help her (when she was about 9), he would agree and then take her out for junk food and bring her back with bags of sweets and pastries etc. Any time I would try to have a discussion about helping her with the problem he would belittle or dismiss my concerns. I now realize it was because she was eating to soothe as he constantly put her in the middle of any argument. This is what made me leave, she actually at age 11 outright asked me to leave him.
I read loads of info about post divorce relationships with non-resident parents, and encouraged an ongoing relationship, but she ended up self-harming a few months later. I took her for therapy, and thank goodness she stopped, so have been listening to her concerns a lot more seriously since then.
I know his new relationship is none of my concern. And I am fully aware that she is merely his next victim, none of my business. Quite frankly if a woman is stupid enough to get engaged and plan to marry a man who she has only met once and knows via the internet, then she clearly has some issues herself, and they can make each other misreable. Of course he is 'Mr Wonderful' to her and everyone who wants to buy into it, but I will never again trust a charming man.
My 'moment', was: He had come round to discuss financial arrangements as DD has changed a few hobbies etc. He was far more 'challenging' than he had ever been before and started using words like 'I won't fund your lifestyle' (assume single mom in full time job without much style in my life). Up till this point we had always had a reasonable relationship post divorce, I made an effort. For example we would be able to have a cup of tea and a chat about stuff, he would often invite me to Sunday dinner when picking up DD, and I made an effort to include him in birthdays and other celebrations and school stuff. After he left, I turned on fb to see his new relationship status, I was very offended at him not giving me heads up (no need to discuss why or whether he had to, as a friend I would have expected more respect, but I realise I do not necesarrily deserve it, plus witholding information during our marriage was part of his abuse). The way he had handled this event/episode brought back all my anger, his abuse style of witholding information and attacking me verbally ,on a different matter to divert attention from his real purpose, so I stupidly poured my heart out in a message to him about how he never cared for me etc etc, I have apologised to him since. It was my 'Bridget Jones moment' and I am over it, it was stupid etc etc.
With him leaving the country it is a relief, but brings financial concerns for me, so have started to look at my legal options, especially as he is going to a country where middle aged white men have a very tough time with finding a job. But my options are limited.
My biggest concern is my DD. She is carrying the guilt of him blaming me for their relationship breakdown. I have attempted to reassure her that I don't mind being painted as the embittered ex, but that seems to be her main concern. I don't know if I am doing the right thing. He is choosing to have this whirlwind romance and move to another country. He has chosen to see me in one light only. I realise this suits his purpose, and I think the new woman, (who I don't believe was around beforehand, that was more a case of using prostitutes as I found out toward end of marriage, think he may have had affairs earlier on, but no proof) is a bit jealous of the relationship he and I used to have. She has been trying to make contact with DD on her own, which really angered me as DD had just found out ex got engaged and was still absorbing info.