frustrations of a manager

today i had another resignation. every time someone tells me that they are leaving, i feel like it's somehow my fault. an article i once read said, people leave managers, not companies. and sure, i'm not saying i'm the best manager. i have a lot of things that i have to improve on (just ask MY manager). but one thing i pride myself is in taking care of my direct reports. so it somehow pisses me off when someone just leaves without giving me a chance to do something about their issues. i'm not saying that there really is something i can do about it. sometimes, their issues are just beyond my control. but what i am asking for, is for them to give me a chance to do something about it. if i can't change anything then they will have my blessing to leave. at least i got a shot at making them stay. ahhhh... sometimes, it's just frustrating to be in this position. but then again, i guess this is part of the job.