The question "Why is this happening to me?" can be a soul expanding question when we ask it in humility and learn what God wants us to learn, sometimes that question can become debilitating if we ask it in shame or embarrassment or anger.
It is easy to believe that your trials come because you were faithful enough. If only I had enough faith, if only I was more obedient, if only I had a stronger testimony.
Prior to a major trial, you may have felt confident in your faith and testimony. I know that prior to my divorce I felt like I had unshakeable faith and never ending courage. In spite of the difficulties of my marriage I felt like if I pressed forward with faith my marriage could be saved and we could be happy. When that didn't happen, you can see how my faith might have been shaken.
After my divorce I constantly questioned my testimony and my faith. In fact, three years later and I am still questioning my faith and testimony. Is it strong enough? Do I really believe what I say I believe? Do I have an unshakable testimony? Do I have enough faith?
Satan wants us to believe that our faith isn't strong enough. He wants us to think our testimony isn't good enough. But those are lies.
No matter the source of our trials, whether caused by our own sin and weaknesses, the sin and weaknesses of others, or simply this fallen world, the Savior's atonement can strengthen us.
Maybe my testimony wasn't as strong as I thought it was. Maybe I don't have as much faith as I thought I had. But if I turn to the Savior during my trials my testimony and faith will be strengthened. As the father in the New Testament pled with the Savior, "Lord, help thou mine unbelief" so, too, can the Savior help strengthen our faith and testimony.