What to do when you regret sending a text?

This guy whos a player kept texting me even though he had a girlfriend. Saying stuff like 'I know it's bad but you turn me on' (a few days before getting engaged) Its a fact that he hates being ignored and when I didn't reply to his texts he would Facebook me. I gave in by replying, then eventually he didn't reply back , now I regret sending that text. If I don't contact him AT ALL now, will he wonder where I am?
What to do when you regret sending a text?
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