For example If you and your ex text or speak on social media every now and again. It would now and again. It wouldn't be a big deal if the ex ask if you're dating someone. Why does my cheating ex keep asking if I'm dating? Which he made up because it was not true and he had no evidence to back up that claim.
Someone who is stuck in the past will never be able to focus on their future, which could mean trouble for your new relationship. Holmes Hahn says that one open conversation about your exes should be more than enough to carry you both through the first few months of your relationship. An open and honest conversation about the topic early on will create a sense of intimacy between you and your partner.
The ex talk is definitely something that should be taken seriously so, when the time comes, both you and your partner should be ready and willing to open up about it.