God uses trials to sweeten us.

And we know that God causes all things to work together for good to those who love God, to those who are called according to His purpose. Romans 8:28 NASB

This is a very familiar verse to me. I have known it since I was a child. But it took many years to really grasp the significance of what it says. When God says something, we know He means it. He doesn't say things lightly or jokingly.
So when He says that He uses 'all things' to work together for our good, then we can be assured that is exactly what He means. ALL THINGS. All things.

Death of loved ones. Rejection by family. Betrayal by friends. Financial difficulties. Sickness and disease. Chronic pain. Job troubles. Past abuse. And so much more.

These are hard things. But they can all work together - like ingredients in a cake - to make you a sweeter person. A cup of flour is pretty hard to get down, a cup of cocoa is even harder! So bitter! But mix it with the flour, and an egg, and some even more awful baking powder, etc, and soon you have a delicious chocolate cake!

This is how trials in our lives work together. We can sit and taste the cup of cocoa on our tongue for years, every day tasting it again, and every day just as bitter! But when we see that God is using it to make us sweet, we can trust Him with that pain and allow Him to use it in our life story.

The condition, of course, is obedience to God's commands. 
...to those who love God...
We know from 1 John 2:3-5, that we prove our love of God by our obedience. So then, this promise is for those who obey God. If we are walking in disobedience and living for Self, then we cannot claim this promise. Only those who truly love God can be assured that everything in their life is working together for good.

How do we get past the pain?    We obey God's commands.
We forgive those who have wronged us.   Luke 6:27-28
We are loving to the unlovely. Matthew 5:44
We depend on God for our livelihood.  Luke 12:28
We give thanks in all things.  1 Thessalonians 5:18
We pray fervently for each other. James 5:16

So be encouraged, my friend! Those hard things in your life are working together for your good. Maybe it seems impossible now, but one day you will look back over your life and understand that through the hardships, you have become more loving, more gentle, more kind and understanding because you were tested and found to be sweet. Instead of bitter cocoa and dry flour, your life will be like a delicious slice of chocolate cake, to everyone who meets you.