Maybe he needed such bolstering, but the conversation just didn't square with Scripture. In my 44 years of reading and studying the Bible, I've never come across any instances of the Lord telling people to feel good about themselves. Yes, He told them that He loved them, and even that He would work through their weaknesses and failures for His glory, but He never so much as suggested that we have any worth apart from Him. As a matter of fact, the apostle Paul wrote about the things that, prior to his conversion, gave him a sense of self-esteem as if they deserved only contempt.
3 For we are the circumcision, who worship by the Spirit of God and glory in Christ Jesus and put no confidence in the flesh— 4 though I myself have reason for confidence in the flesh also. If anyone else thinks he has reason for confidence in the flesh, I have more: 5 circumcised on the eighth day, of the people of Israel, of the tribe of Benjamin, a Hebrew of Hebrews; as to the law, a Pharisee; 6 as to zeal, a persecutor of the church; as to righteousness under the law, blameless. 7 But whatever gain I had, I counted as loss for the sake of Christ. 8 Indeed, I count everything as loss because of the surpassing worth of knowing Christ Jesus my Lord. For his sake I have suffered the loss of all things and count them as rubbish, in order that I may gain Christ 9 and be found in him, not having a righteousness of my own that comes from the law, but that which comes through faith in Christ, the righteousness from God that depends on faith— 10 that I may know him and the power of his resurrection, and may share his sufferings, becoming like him in his death, 11 that by any means possible I may attain the resurrection from the dead. ~~Philippians 3:3-11 (ESV)Despite all the reasons Paul had to pat himself on the back, he knew that he'd be better off dwelling on the righteousness that Christ had given him. His pedigree and accomplishments made him successful in the sight of his First Century Jewish culture, but he disdained them in the light of the Lord.
I don't enjoy facing my many failures, admittedly. Such confrontation hurts my pride! But that pride needs to be wounded, and in fact that wound must be mortal! Self-esteem will keep me from acknowledging my dependence on the Lord, therefore robbing Him of the glory. It will prevent me from looking to Him in my failures and therefore watching Him turn my failures into His successes. Please...if I feel like a failure, don't decide that you'll best demonstrate compassion by building up my self-esteem. Instead, direct me back to the Savior.