During the course of all relationships, people make one of two mistakes:
Mistake #1: Being too focused on yourself and not focused enough on the other person. The tough thing about relationships is that you are no longer the center of the universe. You have to find a way to share that spotlight with another person. For many people, it is difficult to remember that and so you subconsciously (or not so subconsciously) keep the spotlight trained on yourself, to the neglect of your partner. No matter how understanding the other person is, or how much they are too focused on you instead of themselves (see Mistake #2, below), it will eventually sow the seeds of conflict that, if not weeded out, will choke the relationship’s growth.
Mistake #2: Being too focused on the other person and not focused enough on yourself. This is the situation where people end up in abusive or co-dependent relationships. For any number of reasons (“I don’t deserve love”, “He’s so good to me”, “He’s so great in bed”, “That’s my role in my culture”) some people put up with an unbelievable amount of crap in a relationship, being subservient to the wishes and desires of their partner, tolerating unacceptable behavior and feeling meek and miserable about it. No matter how great that other person is or how fearful you are that if you leave, you’ll be alone, people need to stand up for their rights in a relationship, for their dignity and equality.
There may be some people who manage to make both mistakes in a single relationship, but I think generally they are more likely to be inclined to one or the other mistake. They good news: we can correct the mistakes we make and even if we have to do so several times before learning our lesson, we can learn the lesson and go on to a much healthier and happier relationship.