Positivity and negativity is spread all of the universe- started with God and Lucifer.
Attaining equilibrium in both of these things is impossible because equilibrium is ideal situation that's why there is imbalance between both of them and that's what make life more interesting.
Negativity and positivity both takes energy. The best thing which we can do is the same as you have mentioned that we should invest the energy in right direction.
I also always try to use the path of positivity and try to overcome all the negativity with my positivity. My optimistic approach always gives me spirit to excel.
I wonder though, how do you stay optimistic, what steps do you take and what happens if you cannot achieve it?