It seems we all have this problem.
All we can do is ask the Lord to help us. He only can reveal to us the true purpose of all these.
Here is my viewpoint
Initially when God created the world, He created time (day and night) the inanimate objects (stars, earth, planets and other things) plant life, animal life, human beings (in His image, as that of a dominant species as a steward of all His creation)
But humans started misusing their position. They became violent and sinful. So God decided to end the world, but He still saved Noah. Noah started the sacrificial system. (Or was it Abel).
We find sacrifice offending, because we are against killing animals. But for people who do eat meat, sacrifice is ok, because eventually, they will kill and eat the animals themselves. I do not know if the sacrificed animals were eaten by men.
But sacrifice was ended by God Himself through Jesus. But even after that humans continue to eat meat.
We all avoid meat, because God only opened our eyes to the sufferings and we had the heart to change. If God did not give us the heart or mind to understand this, we all would have still continued on our meat eating ways.
On the issue of Crusades, Spanish Inquisition and all, this all happened because, Christians started giving more importance to church dogmas rather than Christ. Christianity had evolved to yet another religious system. Christ Himself did hint that He may not find true faith when He returns.
Little children dying, innocents getting killed, almost all these events are initiated by humans themselves. War, terrorism, etc are all caused by humans. There are natural disasters. But God has even helped us here. He has given us the wisdom and ability to predict them now and thus save ourselves and others.
We give a lot of value to life. We often forget that after life on earth, we will have a much better life with Jesus. But bereavement is really very painful. But here also if we turn to God, He helps us.
Regarding big bang theory, it is estimated mainly based on the fact, that stars and planets are moving further away similar to what happens during an explosion. Most of these data are estimated. So how true it is cannot be verified. If really there was a big bang, what used to be there before it exploded. If God did not create the Universe, then what might have been there could have been just empty space. I find the structure of matter too complicated to have been created by itself. Living things are even more complicated to have been evolved. If everything originated from bacteria, how did it know that it had to reproduce to ensure the survival of the species. Why did it not go for an everlasting life for its own survival.
People generally tend to believe the current norms without questioning. Same thing used to happen in ancient days when people used to believe that the Earth was flat. In those days, people used to accept religious teachings blindly. Today people tend to take scientific finds blindly.
I am sorry, if I have offended anyone.