I think it has to be the combination of "anger and helplessness". The worst part about this combination is that you know that nobody can actually help you and hence there is no use telling your problem/feelings to others. Also, most probably the answer you will get is "things will get alright" which when you hear you know is crap. This suffering is almost always alone. And in most cases, the healer of this is time. Because as time moves on, you start getting on or get absorbed with other things in daily life and this combination of feelings takes a back seat for good. Once you are through this deadly concoction of emotions sucessfully, you become a stronger person than before, ready to take on more of life's hits with grace and ease.