Many years ago a scientist friend told me it is very important to look at all sides of whatever is being examined. A garage, for example looks different when viewed from the side, or from the back or from above. Of course he was right. Suffering also has multiple sides. I don't know enough to comment on all of them, but I can maybe shed some light on a few.
The Church talks about the "mystery of suffering", which suggests that some part of suffering is going to remain a closed book for us. Getting comfortable with that is not easy for some people, and I do sympathize with them, but one of the developmental tasks for growing up spiritually is to face the fact that we don't know everything! And more, that God is under no obligation to tell us.
"When I lay these questions before God I get no answer. But a rather special sort of no answer. It is not the locked door. It is more like a silent, certainly not uncompassionate, gaze. As though He shook His head not in refusal but waiving the question. Like, Peace child, you don't understand." (C.S. Lewis)
So, one side of suffering may remain a mystery. Even if we assign an explanation to it, we will probably be wrong. A mystery isn't a mystery if we can explain it!
Another side of suffering always has a logical explanation. We will post that side tomorrow.