You tell them that you made the biggest mistake of your life. Tell them that you realized this after being alone to your thoughts and not driven by the actions around you. Tell them that you would prefer to have them as a friend if you cannot be together again, of course that is not entirely true, however, you say it anyway because you do not want them to think after hurting them it will just happen overnight.
After the big speech, you do not push or plead, you leave it alone for them to think about you, after all you planted a seed, sometimes you need patience for the plant to grow. Just call them up from time to time, quick and easy calls, the ones that say, I care about you. If the person is difficult, it may take time. If the person has not moved on already, then they will come back without much of a fight, if they have then that is just that, but timing is the key, because if someone truly loves you, they do not move on so easily.
Do not play games when you mess up, just be honest and vulnerable, it normally works.
Just be patient and wait until your ex gets in touch with you, if after 4-5 weeks you do not hear from him or her, just say ‘hi, thought about you today’ and leave it right there, if your ex is interested, they will reply. If not, then good riddance.
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