A person weak in their own faith and understanding isn't likely to do much to encourage someone elses faith. If you don't have your own faith how can you expect to build anothers?
I get the questioning. I've had a lot of bad in my life as well, but the whole idea of faith is trusting what you can't see or understand. What his questions and doubts are have been around forever. There is no clear cut answer.
We just live in a world of sin, sin causes sickness, it causes anger, murder and all sorts of things. Things happen. That's why there is a world wide sex trade full of children and young girls starved, drugged and forced into all kinds of perversion. Why does God allow this? Because people have the freedom to do things.
Why does God allow sex trades?
Why does God allow war?
Why does God allow homelessness?
Why does God allow...... you can add 100 more words here. Rape, torture, murder, kidnapping, abuse, premarital sex, cancer, diseases of all kinds. Because we have free will. And we live in a broken world, in broken bodies and minds and hearts.
There is no answer that will satisfy that question, we just have to have faith that God sees more than we do and pray that the end results will work for the best.