well well well ,the key is --DONT TAKE IT PERSONAL. You may view it as: 此工种暂时不适合你，不等于你的personal failure. DON'T link these two ,then u dont feel so bad.
usa_is_the_best(哦啊啊)
Try to find job fit u and maximize ur talent. 资本社会, 工作的东东应该尽量抽离个人感情,when u work , work like a machine. when u are off , u may dance with ur boss. seperate the two things. That's the professional attitude. G luck ;>