“Honor your father and your mother, that your days may be long in the land that the Lord your God is giving you. Exodus 20:12 (ESV) 
One woman said this about her child, “Time and time again I have patiently instructed the unlovable person in my life. I have rebuked him and taught him, and trained him in righteousness, and still he persists in his sinful ways.”

It is important for us to be patient with the Lords time table for our “unlovable.” Who in Scripture has been pressed and molded according to their own time table? One of our greatest frustrations is that our loved one is not changing fast enough for our liking. We want them to repent now! We want them to change now!

We have to also recognize that some people, regardless of their chronological age have an infant or child’s viewpoint of God and how God is here to serve them, and how God constantly disappoints them.They are like an adult in a 6’ high chair banging their spoon saying “I want my way!” That kind of self-centeredness is very immature.
Sometimes loving the unlovable means holding them accountable. Accountability can take any form you desire so long as it is biblical and intended to provoke repentance and change. For some adult children who refuse to participate in home life it may mean they begin to pay rent in exchange for their inactivity at home. 
If the young adult persists in staying out overnight if they have been out drinking or partying against your repeated counsel and warnings you might consider locking them out. Taking away the checkbook, credit cards, and spending money, and putting passwords on computers and cell phones are also means of providing accountability for certain kinds of irresponsibility. If things are really out of hand, consider a biblical form of intervention that includes the child going to live in a biblically based facility with a program to overcome a sinful habit or life dominating sin. 
In spite of the emotional misery they bring into the family, these people are deeply loved. Parents want them to change as a result of the enforced corrective measures and family members become quite unhappy when all they do seems to have no effect. 
When you have such a person in your inner circle the regular urge is to cast them out. To rid yourself of the trouble they cause you, the heartache. The very real desire is there to make them someone else’s problem. This mistaken belief is that we would be better off without them and the grief and trouble they bring.
If you were to do this, you would be missing out on one incredible journey. God intends to sanctify YOU by their presence in your life. He intends to work in your heart and your mind and to sculpt and chip and hammer away at the rough edges of sin that are in you. This unlovable person is a tool in the hand of the sculptor.
It is critical to remember who is at work in the life of the loved one. God has His own time table for heart change and we cannot hurry Him along! Several of the heroes of our faith were students in God’s classroom of hardship and trial before they were ready to do God’s bidding, so don’t lose heart!
I  learned these valuable lessons (and more!) having had an “unlovable” in my life. I often found myself demonstrating abundant grace toward him. The hope was, the more grace I displayed toward him the greater and more complete the revelation will be when the time comes that he repents. I knew he could be a wonderful manifestation of God’s grace, a living picture if he would only repent, only turn.
My prayers centered around the breaking of his heart for God.  I knew he lived his life for himself and I hoped God would remain long-suffering and patient. My desire was that he would learn to live life for the Glory of God. I knew that he might have to suffer greatly to get there and I trusted that God’s sovereign will would be evident in the end.
To this date, his life has stabilized.  God’s mercy continues to overflow.