It happens that our attention is so absorbed in the past that it prevents us from creating new relationships and living a fulfilling life in general.
However, there are several methods that can help you cope with the current situation.
There may be several options. For example, you can write a letter. Addressed to your ex-partner. Don't be afraid - you don't have to send it at all.
Some people take a more radical route and burn things that remind them of the person as a way of saying goodbye in their mind.
Try to avoid checking his or her social media profile. It is better to delete joint photos rather than admire them. Likewise, you should avoid listening to "your" songs - at least for a while.
Of course, you should communicate not with your ex-girlfriend or boyfriend, but with other people. Try not to be alone, because this state is the best for feeling sad about the relationship that ended.