You'll find your friend to be an emotionally intense, complex person. They're undergoing a time of change, just as you are; but while you're trying to find your rightful path in life, to become the person you're meant to be, they're trying to work out some personal demons. You won't relate to their deepest, most powerful feelings, such as anger, jealousy and fear.
While you have your own feelings that can sometimes hold you in their sway, you are trying to move past them in order to make some personal progress. The conflict you'll encounter in this relationship may not be worth what you'll get out of it. You'll want help from your buddy in finding your proper path, but the help they'll offer probably won't be what you need. One thing is certain: If you remain in this relationship, it will change you. But will the changes move you forward or backward along your path?