The unfortunate truth is that you can’t make someone miss you.
When a person doesn’t want to be with you anymore it hurts.
The only real way to get through it is to accept your feelings. Knowing that the emotional suffering you are enduring will eventually pay off, in the long run, will help your mindset immensely. Growth comes from the pain that you are feeling now.
Accept the suffering and you will improve because of it.
Eventually, someone else will come around that accept you.
Try your best not to focus on what other people are thinking (the person that doesn’t want to see you).
It will only lengthen the grieving/healing process.