Bellamy didn’t even seem conflicted about telling Cadogan that Clarke didn’t have the Key, which could mean that Clarke the leader lost her greatest ally in saving the day, and Clark the woman will have to deal with the emotional fallout of her best friend’s betrayal.
Bellamy’s betrayal could have a major impact on Clarke in two ways: personally and as leader of their ragtag group of friends.
Bellamy and Clarke spent six seasons sharing leadership duties and becoming best of friends despite the occasional massive fight and abandonment, and he has more or less been her person that she can count on.