Its all normal and I’m so sorry about what you’re going through I know exactly how much it hurts its actually one of my biggest fears. Eventhough I don’t want him back, thinking of him with someone else mdrives me crazy but you know what? Right now, they are not with us so they have every right to date anyone they want. Just focus on yourself and don’t let her cause you any more pain. No human in the world’s worth it.