To me, when I see an unsaved person going through a really hard time, my heart aches for them. I can't imagine having to go through those kind of things and it having no purpose at all. In fact, lately I've been seriously considering using this as a way to tell people about our Lord. Simply beginning by asking them, "If you're going through a trial, which would you prefer? To have it mean something - to have a wonderful purpose in your life, or to have it be totally meaningless?" I can't imagine anyone saying they'd rather have them mean nothing in the bigger scheme of things, can you?
All this ties in with knowing that our God, the God who loves us and died and rose again to save us, is in control, and He is using whatever has happened in our life for our good, to make us more like Jesus so we can have an even closer, deeper relationship with Him. In other words, that boss who fired you, or who won't give you the raise, or the teacher who hates you, or the accident that injured or killed your loved one, wasn't a surprise to God. He didn't suddenly give His control of everything over to anyone or anything else. He has either caused or allowed this to happen and He will use it to make you the very best you can be, to make you more like Jesus. He's doing that because He loves you and wants to have a deeper, more personal relationship with you.
So when trials come, your job is to trust Him, knowing that He will take care of you. If you lost your job, He will be your provision and will give you another job at the perfect time. If you're ill, or in pain, He will comfort you and even ease your pain at times, and will heal you in His perfect timing - either in this life or the next. But either way, He will take care of you.
If a loved one has died, grieve yes. Even Jesus did that! But grieve knowing that this is not the end, if your loved one was saved, then you will see them again. If people are slandering you or treating you unfairly in some way, realize that God wants you to trust Him to take care of the situation. Your job is to continue to trust Him to do just that, remembering that you're to rely on Him and not take matters into your own hands. We're to always have the same attitude that Jesus had, which is shown to us in His life and in the following scriptures. (Philippians 2:5, 1 Peter 2:19-23, Romans 12:19–21, Matthew 5:21–24, Matthew 5:39–42, Matthew 5:44–47) Obviously, it's not easy to live the way the Lord wants us to, and we couldn't do it at all without His constant help and encouragement. Another great encouragement is when we can look back at our lives and see how trials really have made us more like Christ!
Realizing this, we can truly be joyful that our Lord has given a great purpose to the bad things that happen in our lives. “Consider it pure joy, my brothers, whenever you face trials of many kinds, because you know that the testing of your faith develops perseverance. Perseverance must finish its work so that you may be mature and complete, not lacking anything.” (James 1:2–4) By the way, that word, "consider" could also be translated, "evaluate". He's not saying that we should automatically have a feeling of joy when something bad happens to us. He's telling us to look at the situation and see it from an eternal viewpoint - how God is going to use it. Then we can be joyful and also give Him thanks which is the other thing He tells us to do at all times: “give thanks in all circumstances, for this is God’s will for you in Christ Jesus.” (1 Thessalonians 5:18) and “Rejoice in the Lord always. I will say it again: Rejoice!” (Philippians 4:4) Notice that we're not told to feel joy about whatever is happening, but instead we're to "rejoice in the Lord". We rejoice because God has saved us and given us a purpose, and even given the bad things that happen to us a good purpose. We rejoice because we now belong to Him and one day this awful sin nature will be completely gone and we'll never have to deal with it again! Just writing this makes me want to stand and praise our awesome God!!!!
