If grace were just for me, and not God’s gift to all in need, I might rejoice in my solo salvation and never be a different soul.

But “the grace of God has appeared, bringing salvation for all” (Titus 2:11)—for every individual, yes—but also for the whole of us as Jesus’ faithful way to live with and forgive each other. 
Grace truly known always grows into graciousness: the living shows we’re starting to perceive how great the gift is. When I extend the grace of God, I take it deeper in my life. When I forgive, I learn how much there is in me that needs the Lord’s forgiveness. 
Grace grows on us, and grows in us, and grows through us. So stay in grace.