When you lose something, think about all the bad things related to that thing and thank Allah for saving you from them. This cools the pain of the heart. You’re not claiming to make a “fair assessment.” You are just reminding yourself of how losing this painful thing is good for you. It might be the opposite for someone else, but for you, you’re better off without it.
And likewise when anything comes your way, think of all it’s good so as to be content. Again, we are not asked to do an appraisal, but rather to be grateful.
In most cases in life, seeing things as good or bad, and being happy or miserable, is totally our choice. It’s easy to be miserable. But it takes a deliberate effort to see only the good in what we get, and see what we’ve been saved from in what we lose. It makes me think of the verse, “We guided him to two paths.” Happy and miserable are two paths. You pick your own.
A man once was about to be shown a room. He said, “I love it.” The lady said, “You haven’t seen it yet!” He said, “I know but I already decided I’m going to love it.”