Why we love a person has a profound effect on how our relationship will progress over time. If the reason the reason you love your spouse is based on their looks, popularity, their financial success, or on what they do or can do for you, over time the relationship will bear that out and suffer or end.
The same is true in our relationship with God. If our love and affection for God is grounded in His blessings or what we think He can do for us, our relationship with Him will be fickle at best and disappointing at worst. The lesson from Job is that we need to be learning to love God for who He is, holy, loving, and righteous, if we are going to have a healthy deep relationship with Him. Love’s love is the holiness of God.