Hurt - Probably too late now, but I agree with DV.
I would have responded along the lines of "Kids had a good day. All tucked up now" and leave it at that. Short and to the point with no opportunity for continuing the text chain.
Your W might have been a rubbish mum. She might have torched your past and did (is doing) some unspeakable things but she is still their mother. If she takes the time to ask about them, then as hard as it is to do then you should send something back. It is not your job to build bridges between her and your children. But it is your job, as a father to at least support her if she wants to have a relationship with the children.
My H is away with the children on holidays at the moment in Mauritius. It hurts like hell. This is somewhere we go in Feb every two years or so. Each day they have been away he has sent me pictures of the children swimming, paragliding, eating etc. He is never in the pictures and there is never a lot of commentary. Just short facts: "D12 enjoying the pool", "view from the room" etc. I never respond to these texts other than to say thanks. At night he sends me a short text saying they are back in the room if I want to call. He never speaks to me during these nightly calls but I can hear him in the background reminding them of things they did that day so they can tell me. This is not cake eating. He can be a [censored] of a H, but he is a good father.
Don't encourage but don't discourage. This is the high road. It is tough because it requires you to put your own feelings to the side.
PS - this doesn't mean I in anyway think you should be having family days out or meals together. If your emotions are still tied to her emotions, then minimize the time you spend together. I just think that texts about the kids get responses.
