Leaving someone on read in the middle of a hard conversation is a reply too. Make sure it’s the one you mean.

Going silent in the middle of something hard still sends a message, just not one you picked. The other person is left reading the gap, and a gap says whatever they are most afraid of: that you are done, that they went too far, that this is how it ends. Absence communicates whether you want it to or not.

When you need to stop, say you are stopping and roughly when you will be back. Even one line about needing until tomorrow keeps the door visible. And if you did mean silence as the answer, make sure it is the answer you want standing.