Help! Moving back home

I don't know if this will work on this situation but you can try. 

Go to your saves folder on your Documents / Electronic Arts / The Sims 3 , see if you have a file in your saves folder that has the exact same name as the game you're currently playing but ending in .backup  If you do, then copy the files in that folder and replace them with the ones on the folder that has the name of the game that you're playing but ending in .sims3  After you do this, the game should load normally. 

If this works, it will load the game a little bit earlier then when you last left it, I don't know if it will load on university or before your sim went to university. If it loads while still in university or if you want to send your sim to university again, then please take note of this: transfer any pictures that you have on your sims smarthphone into the personal inventory (the pictures will disappear if you don't), do not invite anyone to the graduation! On the day of the graduation have your sim be in front of the doors of the Schmidt Memorial Stadium & Annex - Stadium by 10 a.m. (make sure to pick up your mail from the mailbox before) this way when the graduation ceremony begins your sim is already there and can avoid problems of not being able to go inside because of all the sims standing outside.