Most Helpful Guy
Basically don't put all your eggs in one basket. By that I do not mean play the field, but I mean try to keep a healthy balance in your life where you have other things going on as well.
The more you invest in someone, the more you stand to lose. On the other hand, the more you stand to gain as well.
But since it's an investment, there is no need to be rash.
Most Helpful Girl
keep your options open that way if he IS seeing or talking to someone else you won't care too much. hope for the best expect the worst.