My Aunt (married, not blood) is one of these people who likes to post absolutely everything on FB. From pictures of her child in hospital, to posting statuses pleading poverty, if my family members are sick to the yearly tagged picture of my dad's grave. Sometimes she just randomly posts a picture of 'we popped down to see John, we still can't believe he's gone and they'll always be someone missing in our lives' etc etc. It really ruins my day, as the last status/pic she posted I was out celebrating with friends.
I think it grates on me due to the amount of sympathy she gets. It was my dad, he died ten years ago, we're managing to carry on in life so i'm sure she can as she only saw him a few hours a year at best. It's like she really enjoys the sympathy and if her kids aren't sick, or if the car isn't broke the picture of my dad gets pulled out to get her dose of attention.
Also, where do all these people come from with all the sympathy?? She'll easily get 30 comments with people popping up if she needs to talk, or how kind she is. She literally posts various statuses three times a day attempting to get attention. Surely if people stopped pandering her she'd evidentially get bored and do something else with her time.