Loss and gain go hand in hand, don’t they?
Whenever we gain something, we lose something, and vice versa.
Perhaps you gained a new perspective on life, and therefore you lost your old way of being. Perhaps you gained a healthier body, and you lost the old pains that accompanied you everywhere.
Indeed, you can lose an old bad habit, and gain a new relationship with your friends. Loss is not always bad, and gain is not always good, but they always come together.
Just remember that the next time you gain or lose something.