I don’t think it is wrong to be angry with HAshem, just as a child can be angry with his parents, when they have to be strict and say NO to us…at least when you are angry, you still recognize “HE” exists…being angry and still believing is HUGE!
I don’t think letting HAshem know you are angry is wrong..of course he already knows that, but speaking to him in your own words can do wonders….Breslovers try to do it every day….