Sometimes we create our own heartbreaks through expectation. We should have expectations, but and there is a big but, we are all human with human flaws. Disappointment is one of the most familiar feelings, disappointment in one's self, disappointment in other's. Disappointment will happen.
You can't just give up on someone because the situation's not ideal. Great relationships aren't great because they have no problems. They're great because both people care enough about the other person to find a way to make it work.
When someone does something wrong, don't forget all the things they did right.