Im on xbox and i banned messages and party invites from anyone who wasn't on my friends list about 6 months ago. its been bliss..

Its in your privacy settings. just got to messaging options and select friends only. I done this as i was fed up of getting party invites from people at the start of every game and rage mail when we lost. Virtually everyone who messag4ed me after a loss had way worse stats then me so the urge to message these guys back and call them dogshit at the game was very strong. but i didn't do it as xbox are ruthless now about trash talking. They will ban your arse for simply saying the F word in a message to another player. So i just don't bother anymore.

I do like to send people nice messages after after we win and i see someone make an awesome play. they can't messageme back but its nice to know i made someone feel a little good. Some Reinhart done an amazing shatter earlier on eichenwilde and virtually wiped the team himself. i sent him a nice message about how that was the best earthshatter ive seen in ages. A worthy potg for sure.

Just ban messages/party invites from anyone who isnt on your freinds list. My user experience has got so much better since i done this.