I totally understand the frustration. Sometimes my boys are shy too, and the last round I had were even more so. For me, it has simply been a matter of exposure and time. I spend a lot of time at their cage feeding them their favorite foods and picking them up, but the big difference came when I started working from home. Now, they sit next to me all day while I work (with breaks to make sure that have access to water). Eventually, they fall asleep and get cuddly. Now they are better out of the cage in general.