John 15:5-6 "Yes, I am the vine; you are the branches. Those who remain in me, and I in them, will produce much fruit. For apart from me, you can do nothing. Anyone who parts from me is thrown away like a useless branch and withers. Such branches are gathered into a pile to be burned."
Jesus made a very strong statement here. He said that anyone who parts from Him is thrown away and cast into the fire. Why would He make a such statement if it weren't true? It is not for me to try and figure out those who would depart from Him. All I know is what the Word says. If anyone chooses to abandon their relationship with the Lord, they are no longer His children. Those who part from Him are useless and they wither away and die.
On the other hand, those who remain in Christ produce much fruit because Christ is in them. We don't always see the fruit we produce, but He does. Sometimes others can see what we can't see. And, sometimes we are able to see some of the fruit we produce. If we are in Christ, we gladly do what we can and let Him be honored and glorified through us. We don't focus on the fruit; we focus on Him. It doesn't matter how much we see. It doesn't matter if we see any at all. All that matters is that Christ be seen in us.
Be assured; if you are living in Christ you are producing much fruit. Your life matters and what you do through Christ matters much to God. Remain faithful to Him. Continue to live in Christ and great will be your reward in heaven. Apart from Christ, the soul will spend eternity in hell with all those who reject Him as the resurrection and life.