Does Facebook hide certain public page comments from others?

[Md]

i think it's a huge issue. i posted and commented sensitive stuff in a public group about my mental illness yesterday, thinking only people liking that page would see it in their news feed. A good friend told me it appeared on his news feed (not liked the page), had to delete my post and comments... didn't feel like having random 'friends' read about it. really limits me now as it helped me a great deal to have a group of people in similar situation to share experiences, knowledge and thoughts with