https://www.buzzfeed.com/krystieyandoli/whats-the-most-annoying-thing-ross-did-on-friends

WERE they on a break?!

One of the most annoying things Ross had done was in the season 10 episode where he's dating Charlie and Joey and Rachel (who were briefly a couple) come over for a double date.

Ross pretends that everything's "fine." He overdoes it trying to convey that he's okay with Joey and Rachel being together, getting louder and more annoying as the night goes on.

Eventually, Ross breaks down and admits he's not okay, but he really pushed the annoyance factor in that episode.

http://screenrant.com/worst-lead-characters-in-good-tv-shows/

Ross Gellar is the very definition of awful. Everything about him screams “please, slap me across the face and just shut me up already.” The paleontologist starts off the series as Monica’s whiny brother who can’t stop pining over his high school crush, an obsession that at points in the series escalates to just plain creepy (like when he tricked Rachel into staying married to him– because that’s a totally normal and acceptable thing for a person to do). Although all of the Friends gang have been known to complain more often than not, Ross takes this to a whole new level with his constant bitching. On top of all of that, Ross is also homophobic and sexist—he worries about his young son playing with a Barbie doll and hates the idea of hiring a male nanny, among many other instances of general prejudice. Although his relationship with Rachel has long been lauded as one of the most romantic pairings on television, we just can’t see why she would ever want to end up with someone as awful (and unwilling to accept that it’s still cheating even if you were “on a break“) as Ross.