Homeowners do have a positive duty to ensure that their premises are safe for those who visit, particularly invitees as the writer appears to have been. This duty, as in all things legal, is tempered by reasonableness. 

Just because I visit a friend, it shouldn't preclude a legal remedy if I am injured on their property due to their carelessness. It is, as always a sliding scale. Mere bruises shouldn't warrant a law suit, broken bones or other serious injuries are another story, for example what if she had been paralyzed because the friend had let ice buildup over months on a dimly lit porch precluding her from seeing the danger? 

Posting comments about suing on Facebook while not particularly temperate are likely a reflection of being hurt and angry.