We've only been married a year and still in the "honeymoon phase." However, every now and then we have an issue where we are surprised by the other's reaction or upset about something because we don't understand why the other said or did something a particular way. The hardest thing is asking for what we need or want without feeling hurt because the other didn't know. I recently was kind of mad at him for several months because in our huge house of 6 bedrooms, none was designated as my studio (I'm an artist). We moved in a year ago just before we got married and he designated 2 bedrooms as his daughters' even though they don't live there. Another room was a guest room and another was his "mom's room" and she doesn't live with us either! I finally (after getting upset) told him what I wanted and he was surprised saying "why didn't you tell me?" I was like, you never asked!
I'm learning how to speak up for what I want instead of waiting for it to be presented to me (and thereby getting hurt when it is overlooked or forgotten).
The hardest part for me is having to consider someone elses feelings with most of your decisions. The perk singlehood had , was it was nice to do what ever I wanted, how ever I wanted, when ever I wanted without having to consider its effect on another person.
Of course, the security of knowing that my best friend is always here for me, does make up for any sacrifices or compromises :)