I constantly find myself wishing an "invisible" status was available. Something that wouldn't knock me offline, since I want my play time to still be recorded and all that, but something that would make me appear to be "away" or "offline" to friends... anything but "in game".
Sometimes I get home from work exhausted and just want some alone time to play a game, but my friends want me to join them, and will complain if they see me playing a game instead. It would make my life alot easier if there was a feature that would let my friends not know I am there without going offline.
Your time will track but you'll appear as offline. Just message your friends back if they message you while in your game session. The last login time is recorded once you log off. You don't want your friends to think that you are ignoring them ;)
I understand though. I have a friend how likes to message me while playing. I find it very annoying.
Currently Playing: Donkey Kong Country Returns 3D, Deus Ex: Human Revolution, The Legend of Zelda: A Link Between Worlds
Why don't you just schedule a time in where you can play with them? Tell them which days you're working and when you'll be free. You could even start a group on Steam and schedule in a game and which time it will be on and have them join.
If they're that clingy to you, though, they could probably find out you're online by checking your Steam profile often and see your hours in games have changed.
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