Get the facts
Have the facts before printing an article:
"Mom is asked to leave gym due to her workout clothes..."
Your article goes on the erroneous assumption that the woman at the gym was fat-shamed. What appears to actually be the case is that the gym does have a policy about what can be exposed on the body - irrespective of body type.
So many social media platforms are quick and desirous to nail someone to the wall for the slightest perceived transgression. Doing so, in fact, is dangerous to society by ultimately leading so many to believe a false narrative.
Treating people reasonably is no doubt a social goal. There are limits, however, to what people should be asked to do where this is concerned. Certainly, social media writers are held to the same standard. Get the facts before writing - and certainly, publishing - an article.