Transitions in life are usually marked by major events, birthdays, graduations, weddings; but the greater transition often come out of smaller moments, when we stop and look at who we are, because each time we see how far we have come, we also see how far we still have to go. In order to fully transform, we might need to free ourselves of everything we’ve been holding on to, to send us on our new path, the right one. But if at the end, you find the person you have become is not the person you want to be. You can always turn around and try again.
I know you wanna stop it, protect her from it. But you're young. You don't see what I see. It's not just that she makes him a better person and she does, but he changes her too. Damon challenges her, surprises her, he makes her question her life, beliefs. Stefan is different. His love is pure and he'll always be good for her. Damon is either the best thing for her or the worst.