A lot of people are taught to think in terms of cause and effect. Cause A makes effect B happen, and this relationship is simple and linear. To solve problems we therefore tend to try to look at the root of the problem, and try to fix what's causing it. This works very well at times for straightforward problems. To add a further layer of complexity, you can even string causes and effects together and have a nice long chain of causes and effects, much like a line of dominoes.
When it comes to people and relationships, however, the linear model of cause and effect tends to stumble and fall to its knees crying. You see, individuals are seldom in total isolation of others (otherwise it would be difficult to have a relationship!). People act within a system of others, and to look at a person without looking at the system that they exist in might mean that it will take a very long time to resolve any problems they have. In fact, the problem that is being manifested, may be more a product of that person's imbalance within an imbalanced system than an actual problem with that person.
A rather neat concept called circular causality, borrowed from family therapy, explains some of this behaviour. Imagine if A makes B happen, in circular causality, B is also a cause itself, and can modulate or perpetuate A. So you get a circle, with A causing B causing A causing B... you get the picture.
This is especially true in children and families. In family therapy, for example, the aim is not to find out where it all started, because that could take forever! Therefore, the objective is not to find blame, but instead to have everyone involved acknowledge that there is a problem and to work towards increasing communication with each other to find a way to deal with that problem together.
I think that in relationships, sometimes people can get too involved with trying to find out who's to blame in a misguided effort that somehow getting to what they think is the cause of a problem will somehow solve it. It's very difficult to find the cause of a problem if the causality is circular. It's kind of like the old chicken and the egg conundrum.
All too often, by focussing on the problem and trying to find a cause that cannot be found, this actually amplifies the problem even further. These are times when it is better to encourage clear communication between everybody involved and focus on the solution. Sometimes this may seem difficult, but I think it is worth the effort.
So instead of trying to find out where all the problems started and how bad things are now, another way to go about things is to communicate as clearly as you can with others, agree that the problem exists, and foster working together towards where everyone wants to be. Deceptively simple!