Words are like toothpaste

Words are like toothpaste.
Once you squeeze the toothpaste out, you can't get it back in.

This is the same for words.
Once you say them, you can't take them back and you can't get them back in.

Metaphor - is language that directly compares seemingly unrelated subjects. This according to Wikepedia.

I was having a conversation last night about a person with such little "tact", delivery of the message, etc. that it causes people to somehow not have any respect for them. Being in the actual line of fire of this person, I know exactly how everyone feels.

Yet, he asks what am I doing wrong? I think, he doesn't really want to go there. But again I hear the words, what could I being doing wrong? Okay, you asked.

Long story short, in the end this person probably didn't hear two words I said. During this same conversatoin I said something like it doesn't matter anyway, the damage is done. It's kind of like toothpaste, his actions and words, once they are out, you can't get them back in. My son said that's a good metaphor, Mom. He can stop me dead in my tracks with a sentence like that! He knows that word??!! Not only does he know that word, he is applying correctly. WOW.

Words are like toothpaste could be a good rule to live by and remember.