Though the couple are happy, the friendship between Marcus and Mac deteriorates.

When he admits his worry that their friendship will deteriorate if the two aren't around, Marshall and Lily promise that it won't happen.

From there, the friendship deteriorated fast.

Sweetland and Webb had been close friends and business partners but their friendship had deteriorated.

Bianca's friendship with Charlie deteriorates as a result of the deception.

In series three his friendship with Cook deteriorates.

The pair's friendship eventually deteriorates into hatred for one another.

Our friendship won't deteriorate just because we're both trying to win a championship.

After the pilot episode, Mike and Trevor's friendship deteriorates.