How can I let go of control?

Thank you for your inquiry and wanting to get down to the bottom of "letting go of control", as you put it.  As you go about reading my response, please keep in mind that since I don't know any specifics as it pertains to your current situation, some of what I say may not be applicable or things that you have heard/tried already.  The other thing that I ask is for you to try to be as honest with yourself as possible.  It may be hard, but in order for us to work on our concerns, we not only have to ask ourself the tough questions, but also be prepared for some tough truths as well.  With that being said, I am going to start my response with this question that I would like you to think about - What is the worst thing that could happen if a mistake is made?

Being a office manager definitely sounds like you have a lot of responsibility and that you take your job very seriously, understandably so!  I would also venture a guess that this can be very stressful.  Sometimes when we take on all of the load, we tax ourselves so much that it starts to adversely affect our mood and subsequent behaviors when interacting with others or even when we are by ourselves.  The reason why I asked you to think about the worst case scenario is that so much of how we - as individuals - go about in the world is dictated by our thoughts.  And if we can start to look at how our thoughts play a MAJOR role in our perception of things, then we can work on changing these thought patterns.  In therapy, there is a concept called "cognitive distortions" and challenging those negative thoughts that look to do just that.  Basically a cognitive distortion is any thought pattern that influences emotion.  Examples of this are "all or nothing" thinking as well as jumping to conclusions.  And what it means to "challenge" a thought is to talk yourself through whether or not what you're thinking is true.  So in your case, a couple questions that you could ask yourself could be - what evidence do I have that this person will make a mistake?  Is there actually evidence contrary to this (i.e.: are there times where this person proved that they can complete the task?).  This could be a good starting point.  Another thing I think will be beneficial is for you to think back to when you first were learning the job; did you do everything perfectly out of the gate or did you learn from some mistakes along the way?  Even though no one likes when they are wrong or make a mistake, but this too could be a good reminder for you. 

Another strategy I would explore is writing out all your actual responsibilities vs. everything else you're doing could also be a good way of pinpointing what tasks other people should be doing.  Once you do that, you could then work with that other person (or people) and train them the way that you would like, so even though you're not technically completing the task, you DO have say in how they learn what to do.  

The second piece to your inquiry around getting mad and frustrated easily is directly tied to this.  Sometimes our bodies give us warning signs, but we may not be aware of them, so it seems like these emotions come over us very quickly.  You can definitely learn strategies in how to read your body cues earlier as well as recognize your triggers earlier on so you may be able to respond differently.  Another thing to think about is - Do you currently have any outlets - whether it's listening to music, walking/working out, talking to friends, etc.?   Having a way to get out all your feelings is crucial in helping to move forward from a situation in a healthy manner.

To summarize, while learning how to let go of control is hard, it is definitely doable.  It is also understandable that in a world where so much of what happens is OUTSIDE of our control, that you would like to have whatever control you can.  My suggestion is that you begin BetterHelp as a way to work through this so you can get a better understanding of your actions and make the changes that you would like to make.