The hole you are in right now is awful.

Maybe nothing others say can make you feel better right now. Time, that old cliche will pass and you will find happiness again. For a start you have two daughters who love you and need you.

I understand the pain of her moving on. What your feeling is natural. The sooner you can move on emotionally from your estranged wife, the better things will be for you. Focus on the fact you weren't right together and unhappy with how she treated you. Making a personnel commitment to letting go of her and treading the long road towards being emotionally free of her will take time. The more you focus on you and thoughts of being happy in a new start, the easier it will be. (not easy at all but easier)

Many people have walked in your shoes before and will in the future. You know the truth, so continue to speak it.

Your estranged wife sounds very selfish and who knows what will happen in her future. It might not be so positive. The new relationship had it started earlier? Will it last?

I hope that you feel better soon. And I know if you choose you will have a wonderful life with someone new, when ready, who will show you what real love is. Your daughters don't seem her priority right now and it's good that they are yours. That makes you strong to be there for them and fight for them when your life has fallen apart. Your are right and doing all the right things. Remember to care about you too.