I'm Feeling Like a Yo-Yo

So, last Friday I was told they hired someone for the job, so I was suppose to go back to my internship hours. What happens today when I came in? Oh, Dawn we need you to temp again because the other girl didn't work out. Once again it is all about me. Well the VP came in to talk to me about the situation, because he feels bad that they "let me go" and then re-hired me for the position I want as a full-time job. He explained to me that basically I am "over-qualified" for the position (yes, one of those compliments with a sting). He fears that because I am a fast learner, and worker (they have worked with me before), that I will get done really fast and have a lot of down-time of doing nothing, which looks bad on the company. Of course in my mind I am thinking I can look busy and do my homework. So, he asked if I wanted to temp again, and he would understand if not, and that I am being put on the back burner while they still interview for others to take the position. The part that I don't quite understand is that they are training me for the job, which is good experience to have no matter what happens, but if they hire someone I will be training the person to do the job that I want. Does this sound as messed up to you as it does me? I figure in a month if they haven't hired anyone I am going to have to give them an ultimatum about this situation. Because either they need to hire me, or I have to look for a part-time job with benefits. Hopefully they will hire me, but for right now it is a negative. Anyway other than this messed up situation that keeps swinging me back and forth between I might have a job, and I might not, everything is going great. I have to work on my paper this weekend which really sucks! Lets shoot for finishing it or minor corrections by the end of this coming month, that means for the next couple of weekends NO FUN FOR ME!