Turning point

Today....I resigned.

However, it's very tough to make this decision. The workplace's good, people's good, i made many friends here. But....I don't see any career path><
If I continue to work here, Maybe my salary will raise a bit, maybe I will be taking up more challenging projects with more responsibilities, but....I will always stick to this account and never have a chance to move out....

How can I tell my manager on this.....
I know they like me, and I just don't wanna make them unhappy for my move...

Anyway, need to be careful this month to make everyone's happy^^