I don't remember how many times I've heard people reflect on the bad hands they've been dealt in the past that make it hard for them to process the present. No doubt I've done it myself (no doubt I sometimes still do it), and when I'm aware of it, I shy away from behaving such any more. It's too easy to use the past as an excuse for not responding biblically, for not growing in Christ, for shying away from relationships, and for whining and complaining about what should have been, when none of this is what makes for healthy interaction in the body of Christ. We sometimes use past victimizations as a crutch; we continue to use the crutch long after the injury should have fully healed. Christians of all people should not consider ourselves victims--I don't care what nasty experience we've had that would seem to say otherwise. Probably most of us have been persecuted, mistreated, misled to some degree...but God in His sovereign wisdom orchestrates our lives and has knowingly and lovingly allowed all these things for our good and for His glory.
One of my hallmark verses is Psalm 119:71, because it validates every difficulty that ever entered my life: It is good for me that I was afflicted, that I may learn Your statutes. I am pretty sure I would still be a lost sinner without hope if it hadn't been for the crucible of affliction, so I am eternally grateful for those things that I found intolerable in the days before I came to know Christ. I am pretty sure I would be a weak, shallow and unsympathetic Christian if I never had affliction from the day I came to know Christ, so I am grateful for those things that challenge my faith ever since becoming a Christian. I'm not saying that I am continually victorious in my view of these things, but if I continually bemoan them, I have not realized their value, and still have a great deal to learn in that aspect of my life.
Every difficulty I endure has the capacity to do me good, in that it should send me to the cross, to put every offense at the foot of the cross and seek His help in learning forgiveness, in learning healing, in learning to understand others, to have empathy, to sympathize with others in their weakness, to reach out to the hurting and the lost, to help the helpless, to heal others' wounds. Affliction should bring me to prayer and Bible study, seeking God's word on every act that confuses me or causes me to stumble. Affliction should bring me to seek counsel when I can't put the pieces together myself. Affliction should cause me to turn to the Scriptures and prayer rather than my own wisdom in resolution of conflict, in anxiety, in trusting God's wisdom and His will, and in setting my own priorities. It should make me more careful that I don't leave a wake of damage behind me which would hurt others like I may have been hurt.
Every difficulty I endure has the capacity also to bring glory to God, in that those who see how I respond might realize that it is only by God's strength that I can respond rightly. My response as a Christian should not be the same as that of an unbeliever, lashing out, attacking, gossiping, and complaining to everyone who will listen. If it is, I am not walking in the light but am walking in darkness.
So those difficulties that would seem to be designed by Satan to damage me can be turned to God's glory in bringing attention to His goodness and His healing power, to His capacity to bring believers through these things and when they have come through, to be better than they were before. If we use these difficulties as excuses for why we can't function well in the present day, for why we don't have a good understanding of biblical truth, for why we are staying where we are and not growing, then that's what they are: excuses. They are not valid reasons to spiritually flounder and wallow in our self-pity. Those things should change us for the better, not for the worse. They should not weaken us, but strengthen us, making us more fit for God's service, better able to glorify Him in the things we think, say, and do, and in who we are becoming. We should become better aware of just what the Bible says regarding our experiences, equipping us to discern truth from error and to comfort and counsel others. We should increasingly use all the experiences that God puts in our lives to better reflect Him, not the world. The past is something that God has given us, it is still ours, and we can use it for good or for evil. Even if we've responded wrongly about something in the past, we can change how we respond about it in the present, and we can use it for His glory in the future.