"I left the assembly some years back under a cloud of guilt and depression. At the time I thought that I couldn't please God and was defeated. I also thought that the assembly was absolutely correct in their teaching regarding holiness and that I was hopelessly awaiting judgment.
"A few months ago someone showed me that the assembly message of holiness was false and that my salvation was secure in Christ. This truth lifted me from depression and allowed me to start reading the Bible again with a hope that I could have a joyful Christian life again. I am now free from depression, but I have no joy in my life. What's wrong?"
I have been thinking about how to answer your plight. I think we can probably lay the blame at the doorstep of the perfectionist, overcomer, higher, inner life assembly teaching. To have the emotion of "joy" we must have victory over sin in the inner man, according to the Assembly. This would mean even the smallest wayward thought that broke into my inner life would be an invasion that would break down the perfect inner life that I had created.
Through morning times, the heavenly ladder, the selfer's prayer, wheels and lines, assembly gatherings, etc., we sought to achieve a "inner reality" that really meant an emotional state of peace and joy. Trying to constantly maintain such a inner life meant I must not "listen" to what is really going on inside and to even deny that any struggle is there at all.
This sets up a very harmful dynamic that either produces a heart that denies the presence of sin in one's life, or a very defeated and discouraged individual who believes they can never overcome. The former become the assembly leaders and the latter become the "faithful" followers. The hypocritical harden their heart's to their own sin (to protect their standing before God) and likewise translate this same dishonesty to defend the group and it's corporate perfectionism. Meanwhile, those who can't simply deny their lack of inner performance become more and more depressed.
Dear wounded pilgrim, you could be looking for the same emotional state of "spiritual perfection" you had while in the assembly. Grace teaches a different response to assembly "deeper life teaching". Sanctification (the process of being made holy) is not an absence of struggle against sin through achieving an inner emotional state.
Understanding a grace-based relationship with God means I can be totally honest with all the sinful desires that may come into my heart and with that knowledge also know that God has the power to deal with it. We cannot expect to "earn" peace and joy by "dealing" with sin in the inner man. We have peace and joy, not by creating a perfect inner reality, but by believing that God accepts fully the way we are and that we are helpless without him.
The practice of a healthy Christian life will not bring the same kind of emotional highs that come from "being caught up into the heavenlies" in some kind of ecstatic worship, but it also won't bring the lows that come when we fail "to get the victory" in maintaining that emotional high.
Grace produces less a concern for our inner state (or our outer image), and more of a looking out to the needs of others (love). Jesus said that happiness is discovered in loving service, as exemplified in washing of one another's feet. Assembly teaching would see this example as proof that our performance leads to joy, but the context of John 13 reveals that the grace of Jesus washing us first (grace-based relationship) frees us from self-concern and fills us with love for others. To the degree you trust the love and power of Jesus to sanctify your heart it will be the measure of joyful liberty you experience.