A Light Bedtime Question

I'm introspective and questioning.  Ah, a gigantic understatement if you ask my husband, who is constantly fielding deep theological and tangled thoughts right as we should be falling asleep.    

But he's out for the evening being awesome and helping with lights for a play- so I'm going to dump my questions on you for the time being.

I've been wrestling with this idea of giving up what we want- but still finding joy- still living life to its fullest.  If I follow God- then I have to acknowledge that life isn't about me- that someone else ultimately has the say in what is right and wrong- and that there is a way that I should live, even if it isn't always what I would naturally want to do.

But then, if you are like me, you can jump to the conclusion that anything that you really desire might be something you are supposed to give up.  [Buying coffee, for instance? :-)] And I don't think that's really the conclusion we should come to either, because if God created us- and if he poured his passion and love into this world- then we are meant to reflect that in the things we love as well- in the things we are passionate about- in our families- in our art- in our work- in our daily lives. 

And I also know that sometimes God wants us to give up something that we only THINK will make us happy- but still some things we give up are a sacrifice.  

I guess I'm asking- how do you discern when "living to the fullest" or "chasing your passion" has become more about pursuing what you want, or more about pursuing what God wants?  

I have a feeling it is a forever balancing act.  But I'd love to know your thoughts.  Help a girl out.