Selena Gomez just can't quit Justin Bieber.

The two seem to be back together after they were caught partying on Monday. In a video obtained by TMZ, Selena is seen clutching and grabbing at her on-and-off boyfriend at a friend's birthday celebration. Earlier in the day, she was spotted riding with Justin on his Can-Am Spyder 3-wheeler.

Last week, Justin posted and then deleted a picture with Selena that he captioned, "Our love is unconditional."