New research suggests post-breakup intimacy might not be so bad after all.
This is all to say, hooking up with your ex does not help you move on physically and emotionally. Although It's completely normal, and fairly common, for people to hook up with an ex-lover because it is something that feels physically familiar, and comfortable.
Although yo-yo-ing relationships are actually bad for your health, if you broke up with your ex it is for a reason. According to psychologytoday one of the best ways to get over a breakup is to see your ex-partner in a negative light.