Sims 3 University game seriously glitched after sim graduated

I really hope that you can help.  I have spent a long time getting my sim to graduate.  She invited her sim boyfriend to the graduation party and graduated as normal and returned to the dorm.  However, it was then that I lost all control of my sim.  Her picture dissapeared and household funds were 0.  I am not able to interact with her in any way.  

She was sat at the computer talking to someone when the game glitched.  Her commands had a red X in them and I was unable to cancel her actions.  She glitched from one computer to another and then I noticed that she did not have the same sim name as I had called her but took the name of another roommate but she looked like my sim.

When the tip came on the screen that her time at university was at an end she did not leave but instead dissapered from the lot and time in university carried on but without my sim or any interactions.

I have tried using cheats to delete objects in use but nothing seems to work.  

I have tried cancelling her actions but it will not cancel.

I really do not want to lose this sim as I have put so much time and effort into her.  Please can you help try solve my problem so I can continue playing my Sim.

Thank you