We should be silent rather than speaking about other people when we are not certain of our facts. We should not act on flimsy assumptions about why people act the way they do.
When we act without knowledge we often end up regretting our speech or actions when the real facts come to light. The damage to relationships both current and possible has already been done.
There is an old Russian proverb that says this well:
Once a word is out of your mouth you can't swallow it again.
We would cause a lot less stress and problems for ourselves if we showed caution in speaking and acting when we do not have first-hand knowledge and we have not checked our information.
We would not like anyone making inaccurate assumptions about ourselves and we should not do that to others. We can certainly be cautious until we determine for ourselves the validity of the information. Silence can be golden.