It's funny, I'm so jealous, yet I pity you. What the hell? lol
Just don't get involved in raiding with a guild. In fact maybe you shouldn't join a guild at all. Then you'll get more friends, have obligations to people like "yeah, I'm free late on Saturday night" and they'll expect you to be there. Don't help lowbies with an instance unless you are seriously considering the next 4-5 hours of your time to be expendable.
Always prepare yourself a lot of time for instances, and if you have trouble on the first few pulls.... bail out because you're with newbs.
Always have an activity to do on your computer while you're waiting for people.. I guess browsing evilbore is a perfect one.
Aaaaaand.... don't raid... lol.
Raiding takes foreeeeeeever. People always say they have the guilds that clear all those high instances in record times and blah blah blah.... Well to be in that guild, you need to raid often.. so WoW becomes a constant weekly thing. If you go inactive, they take away points from you. And you're gonna wipe unless you're with a LOT of people who know how to do those instances and have already been through the hell of learning them.
Just don't raid... waste of fun