These birds are skittish things at best. Don't get frustrated so quickly!

Take your time and go little by little. The G2 sim is a great thing, but it's not the real thing. As close as it gets, there are still other factors that it can't take into account. So, sometimes people get a false sense of security and think they can do exactly what they practiced in the real world. Unfortunately, it's just not so.
It's a good tool to learn on and get an idea of how things work.. but in reality, it take stime to learn how to fly.
Just my two cents.
Happy Flying!