The Principle

The point of co-dependency is the belief that one feels dependent on someone else, or something else, for the feelings they are unaware that they are choosing.
The need for a co-dependent type to feel obsessed with controlling every facet of a "relationship" is possibly for a need to control their own feelings.
The real problem may be that they correctly feel they are not controlling their own feelings. It's also important to understand that it is not that they cannot control, and be responsible for, their own feelings, it is that they won't. They probably haven't been taught how, or even been told that it is possible. Perhaps they have never been told that they actually have a choice.
It is possible that their fears and anxieties about their feelings is due to the fact that they allow anyone except themself to choose how they feel.
They may be allowing themself to feel like a victim because their feelings are based on someone else, or their environment, and it scares them to not be able to "control" anyone else, no matter how hard they try, or even their environment. The truth is: They cannot control anyone else; their thoughts, feelings, or actions. They can only control their own. EVERYONE resists manipulation! In fact, the anger, frustration, and often depression may be traced back to how the co-dependent person is feeling "manipulated" because of their own choice to be dependent on others for their feelings!
The "neediness" component of co-dependency is the belief that "one 'needs' to control OTHERS, in order to control their OWN feelings". I suggest that this belief is not true!  The co-dependent, and they alone, control and create, their feelings, from inside; not outside. NO ONE can MAKE anyone feel anything. They are always choosing their own feelings, based on their beliefs. They may ALLOW themselves to be manipulated into choosing, but the allowing is still a choice. Until they learn that they are choosing their feelings, and that those choices are not really as "automatic" as they have been led to believe, they will not be able to take responsiblity for which ones they are creating themselves and feeling. Blaming anyone else for how they feel is a sign that they are not being responsible for choosing the feelings they want, and are being dependent on OTHERS for what they can really do for themselves, and either aren't aware of it, or refuse, or are not ready, to learn how to do it yet.
My belief is that Step One in recovering from co-dependency is to learn to stop blaming everyone else, and anything else, for how I am CHOOSING to feel; especially ABOUT MYSELF!