Old habits are hard to break, and this relationship doesn't exactly present you with the impetus to develop new ones. Whether this is a harmful thing depends on several factors, including what other aspects exist between you and how they affect you. In a past life, you two were involved -- perhaps romantically, but possibly in some other capacity.
In some way, you brought this person good fortune in that past life -- maybe you gave them a good tip on a bet or investment opportunity, or maybe you were a married couple who increased your worldly holdings through your union. That was a good thing with a positive outcome, but you were also excessive together -- you may have encouraged them to gamble, for example, which can be a destructive pastime even if it's monetarily beneficial. In this life, you encourage this person once again to be excessive, to take unnecessary risks. There may be other ways in which you're extreme, as well. You might have a strongly spiritual or idealistic side that you try to push on your partner, not recognizing that you can teach much better by example than by force. You should both strive to be a good example to each other, and to yourselves. Don't encourage each other to take silly risks that could upset the equilibrium of your relationship and your lives. That would be a mistake that you don't want to repeat in this life.