Happy Monday! Use it if you need it.
Dear Sir or Madam:
While we certainly appreciate your prior patronage of our services in the [month/s] of [year], we must inform you that our ability to communicate in a sexy fashion with you has come to an end.
As we did not enter into a contract or other mutual agreement to “keep in touch,” we must ask you to cease [emailing/texting/sending inappropriate Snapchats].
Please note that as we are now engaged in other obligation/s, any further attempt by you to contact us will result in public Internet scorn by us and/or our associates (colloquially, “friends”).
Very truly yours,
Former Recipient of Your Sometimes-Affections