Friendship is more than certain activities or gifts. Card giving, calls, and remembering things about a friend's life are often what people think of as actions that create or maintain friendships.
It's true that these can help a friendship, but they are not what makes up the friendship. If these are done without love, they are empty, and not really helping the friendship. If a friend senses they're only done out of a to-do list, it'll feel empty.
1 Corinthians 13 says if there is no love behind or motivating these actions, these actions are really nothing of worth. Every person desires to be known and truly accepted, and these actions don't necessarily mean that is happening in the friend's heart.
All of those actions I mentioned are good, but only when they are honest actions, produced or motivated out of love.
This also applies to how we approach God. We should aim to get past only focusing on a list of actions to do, and aim to do things more out of a sense of wanting to truly know God and accept his Word.