Is Justin Bieber, 21, feeling low about where he stands with Selena Gomez, 23?! The singer seemed totally sad while performing his 2013 song “Nothing Like Us,” which is about his split from the “Hands To Myself” singer, at the Montage Beverly Hills Jan. 14, and we can’t help but wonder if it’s because he came to the realization that things are over between the on-off lovers once and for all.