Naomi Watts & Liev Schreiber Breaking Up Is Hard To Do

Naomi Watts and Liev Schreiber may no longer be an item ... but that doesn't mean they've sworn each other off completely.

Liev was seen leaving Watts NYC apartment Saturday just a few weeks after the couple announced their 11-year relationship was donezo.

The two were never married, but have two boys together ... so it's possible the rendezvous was solely kid-based.