Sorry but you can't take back what someone else read before you had your change of heart. People who have read it remember for good or ill. I have seen people deliberately push other posters buttons, even make accusations and personal attacks then re-consider their post and delete/rewrite it leaving their victim looking like the ass hat because they aren't all sweetness and light in response to their tormentor.
A few might abuse the delete, but when you report yourself, a Mod has to delete for you, so you can’t sleaze the whole conversation past them.
Not to strangle you with my rosary beads, but first we “repent”, then we learn to “sin no more”, so in my case, waking up in the morning in a cold sweat over something i posted in the heat of the night, I am happy to delete if I can, beg salvation from the The Gods who Mod, and try to not be post number 666.