Well i believe

"We both contribute whatever it takes to make our relationship successful"

I do not expect anything from my h in return for my sacrifices, i do it because i want to and no other reason, because i enjoy making him happy, it makes me happy to make him happy....

So if making him happy means i have to go to a basketball game now and then, it is not a big deal and i do not expect him to do something in return because i went to the basketball game.....

It is about making the other person happy, not at your expense but because you want to.....

Either way IMHO it is still sacrificing and it is NOT a BAD thing.........