All I can say is welcome to PC and hope you find advise and support here. I have been through a divorce and had a three year old at the time but it was not messy and we are still good friends. There is really no time limit on the grief and how long it takes to get over it. 25 years is a long time. I have heard it can take 5 years to get over that and move on. If it is messy and dragging on in court that makes it longer. My sister is going through one right now with two small boys. It has not been pleasant and hard for all of us. I have always been good friends with her ex and decided I will still remain friends with him and keep it separate. If she is in therapy that is a good thing. If he left her obsessing and being bitter and angry and maybe demanding more than is rational to get back at him is probably normal to a certain degree. 25 years and raising two kids to divorce is a huge change and I would say be patient with her and encourage her to keep getting help to process it all.