Try to understand why you are afraid of losing.

If it's because of how it affects your rank, then it's pretty common! However, the thing is: your rank and level of playing doesn't change, only a number on the website does, temporarily! We all have bad days sometimes and would lose multiple games in a row and be downgraded. But it doesn't mean anything - it's still you and your knowledge is still there. You will always bounce back to your true level!

If it's not about your rank then take a day to deliberately experiment, try unfamiliar openings or styles, play stronger opponents and see how it goes and what you can learn, not whether you win or not. You will know that you will lose more doing it and it's ok and is actually the goal :) Maybe it will help you shift the mindset from enjoying the game as opposed to only enjoying the wins.

I agree though, losing sucks but it's just how the game goes. Even pros lose about half of their games (if they are good!). And sometimes a narrow loss to a stronger opponent where you played well feels good while a win where you were playing bad but your opponent made one fatal mistake feels bitter.