Accepting what is, does not mean being apathetic. I think of it more as being in a place to better deal with a situation. Resisting what is, IMHO, does the opposite.
I like to throw out silly analogies. So I will try again
Let's say you wake up in the middle of the night and you discover the house is on fire.
If you accept the fact that the house is on fire. What is. You get the hell out.
If you resist. What do you do? Tell yourself that the house isn't on fire? You will burn.
BITS
Happiness is not something ready made. It comes from your own actions.