This problem didn't occur until i had to redo the graduation process because my game couldn't save.
Everytime i try to make my sim leave campus a group of random NPC's show up waving goodbye, i assume some of them get in way of my sim when leaving and getting into the moving truck causing her to not be able to go.
then once the loading screen is gone im back in the university lot with a bunch of random NPC's in my control unable to do anything but browse diffrent lots while the face of my actual sim and her moodlets are on my screen and the not the npcs. (Ill put a picture to show you what i mean )

Every time i click on one of them nothing happens. I tried resetting my sim as well as the NPC's, I tried taking free will off before my sim leaves campus, I tried dropping her out of university and changing the dorm in a residential lot but the results stayed the same.
For the graduation i did invite a few people to the campus. I didnt have a problem leaving the first time but i did notice that those characters were still at the campus when i re enrolled, i tried to get them back but there was no luck either. some did got back to the home world but some were stuck.
If you have any other suggestions please tell me. i cant view the home world in edit world anymore. anyways, Thank you!

Never mind i decided to just delete the game. different forums said that there is no other solution. R.I.P game.

If I were you I would have moved the sim into the bin then moved her in the previous save-home world where she just left for uni. Master controller can fix lost relationships if they're lost.
This is my method at least. :\

The thing is i was stuck in the university world. whenever i clicked on the home world it would put me through a long loading screen and the university campus would appear again. Also i couldn't switch residences so it was basically a loop of me having to reload the game and "go home" and get stuck. Thank you though, it possibly would have help if i didn't save the day i graduated. Oh and i was trying to move her out of the dorm but the option didn't appear.