The pastor who performed my marriage and counseled my wife and I before the blessed event gave me this wise advice...Put family events (i.e. commitments) in your planner along with your business appointments. When people ask you to do something when you already have a family commitment tell them "no" just like you would with a business conflict. 99% of the times another time will work out. I do occasionally get some strange looks from young, single, career-obsessed colleagues, but they usually work around my prior commitments without any complaints. As has been mentioned already, it's always instructive to ask yourself what will matter to you in 10 years. I have never answered that question on the side of work.