I know a young woman who was repeatedly cheated on by her spouse. Yet, she forgave him after the first couple of times for the sake of the family. Later in the marriage, she suspected he was still cheating on her and had sex with a young woman who he said he never had sex with. Well, she received pictures and emails from this woman after he swore they never had sex. He was now backed up in a corner, so he finally confessed to her that he was and did sleep with the acussing woman. She told him it was over and that she was seeking a divorce. She continued to live with him while making plans to move out because she and the kids had nowhere to go. While she was still living there, he made several efforts to keep her from moving out and divorcing, but she said she never reconciled with him but they did have sex. After a couple months she finally had enough money to move out and eventually filed for divorce. Does it matter when a person separates from an adulterous marriage? Does it matter when the divorce was filed? Should she be able to remarry?
She divorced her husband because of his continued sexual sins (Matthew 19:9). For that reason she is able to remarry. That a divorce takes a while to complete in most countries does not enter into the picture. And until the divorce is completed, she is still married to her husband, so the fact that sexual relations continued for a while also does not matter.