You won't quite grasp your buddy's innate vitality and individuality. Your deepest source of personal power is quite different from their surface-level strengths, and whether consciously or unconsciously, you'll push them to express those strengths in terms you can relate to. You might try to force them to transform themselves, just as you try to transform yourself, even if they aren't interested in -- or in need of -- deep personal change.
Whether they're outright resistant to your pressure or just oblivious to it, you could react by becoming more controlling in your behavior, leading to an ongoing (if subtle) struggle between you. In the end, you'll both have to make adjustments: You'll need to learn to let your friend express themselves in any way they wish, and they'll need to turn at least some of their focus toward greater self-awareness and personal evolution.