Many modern messaging apps have the "Read documents" option enabled by default. This is a confirmation that is sent to the sender that you have read the message unnecessary source of stress for all concerned. Disable it.
The requirement for read receipt is simple: when you open a text message in iMessage, WhatsApp, or other text-based communication platforms, the sender is notified that you have done so (and probably read them). While some people are very excited about the importance of read receipts, arguing that they lead to transparency and force us to recognize other people in time, we can no longer argue. We are not fans, and it turns out that there are not many other people.
The nice thing about SMS is that it's an asynchronous activity that unlike a personal chat or phone call does not require immediate response. SMS messages give you the time to think about the communication, because the other participant does not know that you are there yourself. You could sleep. You could be busy at work. They could do anything but read their SMS. The read receipt removes the beauty of asynchronism and adds additional stress to the interaction, screaming every time you read a message that you have actually read that message. This is not only stressful for you, but also for the recipient by telling them that you have seen his message. However, due to your silence, you do not answer for some reason.
You can return text messages to their simple roots by turning off the read receipt. Are you using iMessage? It's as easy as opening the settings on your iOS device and disabling "Send read receipt" under "Settings> Messages". You can do the same in the WhatsApp and other messaging apps settings (the setting can be called "reading") Receipts, "read reports" or "see messages", depending on the app.
Once you do this, you can enjoy a stress-free SMS experience and respond to your own time.