Should I text my ex to tell him how I feel?

We broke up years ago, I’m OK and know there are other fish in the sea, but I feel like it was right person wrong time. However he reacts to this information is not that relevant to me. I want to tell him that I still think about him so he knows how I feel. He has a girlfriend though, but I’m not trying to get him back. I just want him to know, if he walks down the aisle with her one day I want him to know his old girlfriend feels sorry for how she acted and would take it back if she could. Should I tell him?
Should I text my ex to tell him how I feel?
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