All of us will have unpleasant experiences in our life. God has not promised us that everything in our life will be positive or that everything will go the way we want it to. If your goal in life is to eliminate everything that's bad in your life so that all is good, you we will miserably fail. No means exist for you to accomplish that goal.
What the gospel can do for you is equip you to have a positive attitude and to maintain a position of faith in God even when things are difficult and bad. There are some things in life that you and I have no control over. What we do have control over is how we respond to and how we react to those unpleasant episodes in our life. We may not always do it when we should, but in Christ, we have what takes to remain positive even when life goes negative.
While Paul was in the Roman jail, others became emboldened to preach the gospel. But not all of those preachers had the right motives. “Some, to be sure, are preaching Christ even from envy and strife, but some also from good will,” Paul writes (Phil. 1:15, NASB).
Needless to say, this was not a totally good experience. But still, Paul chose to look at the bright side of what was happening. “Whether in pretense or in truth, Christ is proclaimed; and in this I will rejoice. Yes, and I will rejoice,” he says (verse 18). This is an example of being positive in a negative situation.
As Christians we have the capacity to respond to negative experiences in positive or negative ways. Paul says, in this matter, I will rejoice. Rejoicing during unpleasant circumstances is a matter of choice. Even Spirit-filled Christians can a have pity-party if they choose to, but they don’t have to.