I don't think a relationship should be hard.... edit
I don't think that being in a relationship should be such hard work. I always thought that if you found the right person, it should be easy.
Not saying that times won't be hard or there will be disagreements but the day to day of the relationship shouldn't be something that you stress about.
For example - one of my coworkers is always worried about her husband being angry and not doing something that would make him angry. my response always is, so what if he gets angry, he will get over it. ( maybe i am not explaining myself well)