it's not what they're getting from it, it's that there's a pretty big community based around pretend mental disorders and it's loving stupid
i don't understand the mindset of pretending to have OCD, glorifying your "disorder", and then calling people ableist because they won't play along
It's also pretty insulting to people who have actual disablities, mental or physical, when people pretend to have them to garner sympathy.
They have no idea what living with those disabilities are like, and if they did have the disease, they probably wouldn't want the attention, or to be constantly focussed on the disease, they'd just want to get on with life.
If you actually struggle through the day with a lot of disabilities, the chronic persisting ones that are always there, then the last thing you want to do at the end of the day is sit on Facebook or Tumblr and moan about how bad you feel.