No one is perfect, and not everyone has to be 100% healed in order to move on to the next relationship. And to be honest, it can make a person feel better to have sex, get attention from someone else, and temporarily fill any other voids that may be there. That said, someone who isn’t over their ex can struggle to form new, healthy emotional attachments. That’s why, as a therapist, I would generally advise against getting into rebound relationships.

It’s important to remember that ending a relationship is still considered a loss. Many people go through the same thoughts and feelings as if someone passed away—therapists call this “the cycle of grief.” Regardless of the circumstances to why the relationship ended, it needs to be processed in a healthy manner. That often means taking some time and space to reflect on yourself after a relationship ends.

I often tell my clients that after a breakup there should be a “detox period,” where it’s all about them. Take as much time as you need to work on yourself: physically, mentally, emotionally, spiritually, and relationally. Figure out who you want to be in the next relationship and take responsibility for your own healing. This may even include getting professional help.

The goal is to make sure you do not bring any of the same baggage from your past relationships into your new one.

https://www.mindbodygreen.com/articles/rebound-relationships