Answer this before drafting anything, because the research on it is uncomfortable. In a daily-diary study of young adults after a breakup, contact with the former partner slowed the decline of love and sadness alike. Staying in touch keeps the relationship's feelings alive on both channels. If your goal is to heal, the honest move may be not sending anything.
There are two defensible reasons to reach out. You want a real read on where things stand, and you are prepared for any answer, including silence. Or the relationship ended around a specific overload, the dust has settled, and you want to reopen a channel without a verdict attached. Both are reasons a text can serve.
There is one common reason a text cannot serve: using a carefully engineered message to retrieve a person. Plenty of pages promise texts that make an avoidant "lean in" or "lose control." That is not how attachment works. A message can lower the pressure that makes an avoidant disengage. It cannot manufacture wanting. If the plan only works when they come back, the plan is pressure wearing a casual outfit, and avoidant partners are precisely the people most tuned to detect it.
A useful gut check: would this text still feel worth sending if the reply never comes? If no, wait until that answer changes.
