If “falling in love” happens, so will “falling out of love.” As C.S. Lewis said, “The great thing is to continue to believe when the feeling is absent: and these periods do quite as much for one as those when the feeling is present.”
It’s all about trusting in God, and not in feelings. Christ-followers are just as apt to “fall in love” as flesh-followers. The difference is the foundation upon which said love is built.
We fallible, human-type beings are going to feel emotions, but we must remember that said emotions are just as fallible as anything else in our lives—probably more so. If we think of emotions as nothing more than a temporary effect that endorphins have on our brains, we may be able to assign a more appropriate priority to them.
Does that sound cold and heartless? Actually, it’s anything but. Think about the “good” feelings you experience after exercise; you feel pumped, ready to take on the world. But what about the next day? You go back to the gym and repeat the process.
The emotions associated with love and hope are similarly transient, even though they effect your life far more profoundly than the generic, “good” feeling from exercise.
What I’m saying is, we must take the sensations of love and hope, and of any other emotional responses to spiritual facts, with a grain of salt. They are the icing on the cake of Biblical spirituality.
We must expect, and guard against, the natural discouragement of failing to see in ourselves all that we want from God. I can think of two Bible passages that bear directly on that: “Hope that is seen is not hope, for who hopes for what he sees?” (Romans 8:24) and, “But do not overlook this one fact, beloved, that with the Lord one day is as a thousand years, and a thousand years as one day.” (2 Peter 3:8).
Remember, dissatisfaction with your spiritual growth is great, but discouragement is from the flesh, and condemnation is Satan’s specialty.