How can you help counselees to overcome (or avoid) mid-life failure?

Teach them these principles from Scripture.

A. Be on your guard.  Paul tells the Ephesian Elders, Be on guard for yourselves (Acts 20:28).  He also tells Timothy,“Pay close attention to yourself… (I Tim. 4:16).  The Proverb reminds us, Watch over your heart with all diligence, for from it flow the springs of life (Prov. 4:23).
1. Don’t think it can’t happen to you.  Therefore let him who thinks he stands take heed that he does not fall.  (I Cor. 10:12)
The scriptural examples of David, Noah, and others; along with men of God in recent years who have fallen should serve as a warning to all of us.  It is possible for a person to have a true walk with God (David was a man after God’s own heart), to be used of God, and yet to fall.   Perhaps Christian leaders are most vulnerable because they may think they are so spiritual that they are beyond such sins.  Beware that Satan will never stop trying to destroy you (I Pet. 5:8).
2. Neglect of the small things can lead to a big disaster.  Just as a newly conceived life in the womb is tiny, sin which is conceived in the heart can seem very small  (James 1:15).  The neglect of private Bible reading to feed one’s own soul or a loss of fervency in private prayer will long be unnoticed by others.  Lowered personal standards for the use of the television or the internet, or indulging private lusts and fantasies can seem harmless.  A man may become slack in his work habits with no visible impact on the results of his job or ministry performance.  Sooner or later the embryonic lust will give birth to sin which has deadly consequences.  Small sins must be aborted in the womb of the heart before they grow to full term.
3. It is possible for a spiritual leader to carry on his official duties with apparent success while harboring secret sin.  David continued to function as king and as judge (II Sam. 12:1-5).  He probably continued to participate in the external rituals of worship (lest he be suspected).  I never cease to be amazed at how fallen pastors can continue to preach the Word of God,  give counsel, and administer the church until they are caught.  An experienced man may be able to fool the people in his church, his spouse, and perhaps even himself.   The ability to go through the motions of ministry reflects a frightening hardness of heart.
4. Remember the consequences of your fall.  Even though David was forgiven by God, he paid a steep price for his wickedness (II Sam. 12:10-15).  Men who stray fail to count the cost to their wives, their children, their personal reputations and to the Name of Christ.   It may take many years for a church to recover from the betrayal of an unfaithful shepherd. His family may never recover.  The man who falls into immorality is like a stupid ox going to the slaughter (Pr. 7:22).  He doesn’t realize the calamity he is bringing upon himself and others.
B. Seek help. Don’t wait for Nathan to appear on your doorstep.
1. Make yourself accountable.  Be open with your wife and with your fellow church leaders about the state of your soul.  Pray with them.  Invite them to ask you the hard questions about your contentment, your zeal, your use of your time, etc.
2. If you are living a lie, come clean.  One thing that grieves me about Christian leaders who have fallen into sin is that they seem to only confess after they are caught.  The cost of exposing themselves seems to be too great.  They fool themselves into thinking they can free themselves from bondage and then to go on as if it had never happened. When David kept silent about his sin he was miserable (Ps. 32:3-4).  When he confessed his sin, God forgave him (Ps. 32:1-2,5)..  Though David despised God, God does not despise a broken and contrite heart (Ps. 51:17). It is better to face your sin, even with its consequences, and be right with God than to live a lie.
C. Remain faithful to your present call.
1. Continue to cultivate the gifts and opportunities God has given you.  Paul encouraged Timothy to “kindle afresh the gift of God which is in you” (II Tim. 1:6).  The fire which remains unkindled will go out.  Continue to make a study of ministry: preaching, counseling, and shepherding God’s flock.  Learn new and better ways you can serve the Lord.
2. Pursue every phase of your life as a vocation from God.  Whatever you do, do your work heartily,  as for the Lord, not men (Co. 3:23).   If it is conquering nations, do it as unto the Lord.  If it is establishing new churches which grow to thousands in attendance, do it to the glory of God.  But if God has called you to something less exciting, be satisfied with the place God has given you and do it with all of your heart. If it was David’s calling in the last half of his life to faithfully administer the land, he should have done it with the same faithfulness and zeal by which he conquered it.  If it is God’s call for you to be a faithful pastor of a small flock, without receiving human recognition, then do it with all of your heart.  If your career has reached its plateau, then serve God in that job with all of your strength.  If you need to find a new vocation, pursue it heartily.
3. Make good use of the time God has given you.  He is not done with you yet.  He has allotted you a fixed amount of time on this earth to serve him. Every hour should be carefully used for His glory. “So teach us to number our days, that we may present to You a heart of wisdom.” (Psalm 90:12)  He has kept you here for a reason.  You may have many more years of fruitful labor ahead of you.  Even though our culture worships youth, Scripture honors the wisdom of those with age and experience (Pr. 20:29).  Pray God will continue to favor your life’s labor and establish the works of your hands (Ps. 90:17).
4. Be determined to finish well.  David wanted to quit before the warfare had ended.  In contrast, the Apostle Paul expressed a passionate desire to complete his race without being disqualified (I Cor. 9:27  II Tim. 4:6-8).  As you see others stumble into immorality, greed, or simply losing heart, pray God will give you the endurance to run with all of your heart until the end, without falling.
D. Find your joy in the LORD.
1. Put off the false hope of satisfaction or bliss from earthly things (Isa. 55:2). Like Solomon in Ecclesiastes, you will discover worldly pleasures and treasures are vain.  If your hope is not heavenly, you will be bored, for there truly is nothing new under the sun.  Deal honestly with your idols.  Destroy them before they destroy you.
2. Cultivate a living relationship with God.  Feed upon Christ as the bread of life (John 6:51).  Be satisfied with the wine and milk which God offers without money and without cost (Isa. 55:1). Be alert to any Pharasaical formalism in your personal devotional life.
3. Be thankful for God’s past faithfulness to you (I Thess. 5:18).  David had forgotten all of the wonderful things God had done for him.  We should follow the pattern of some of the Psalms by continually reminding ourselves of all of the great things God has done in our lives.   He has always met our material needs.  He has blessed us in our homes and in our churches.  His past faithfulness, in the earlier phases of our lives, is the basis for our confidence in the future.
4. Learn the secret of being content in the present (Phil. 4:11f).  Remember God’s sovereignty.  He has given you what is best: your wife, your children, your ministry, your money, your health, your friends, etc.
5. Keep a redemptive focus. Your value and significance is based upon the work of Christ, not your earthly achievements.  Find your delight and identity in what Christ has done for you..
6. Live in light of the future (I John 3:2-3  II Pet. 3:11 II Cor. 4:17-18).  If age 40 were truly mid-life, it would be a crisis.  If the only phases of life which to look forward were retirement and death, you would have cause for alarm.  The believer always has a hope beyond earthly dreams of marriage, children, and vocational success.  One day we will be with Christ and we will be like Him.  The years we spend here are to be spent in light of the eternity we will enjoy in His presence.
7. Your legacy is in heaven.   If the Lord tarries, you almost certainly will be forgotten after two generations pass (Ecc. 2:16).  Earthly treasures and reputations are fading.  Store up treasure in heaven which is secure and eternal! (Mt. 6:19-21).