Dialog 1 Out of sight, out of mind [ 去るものは日々に疎し ]

Yukio:How's your long distance relationship with Wang going?
Angela:We decided to break up. I lost interest in him after a while. Actually, the feeling was mutual.
Yukio:You guys were such a good couple! I'm sorry to hear that.
Angela:Well, you know what they say, out of sight, out of mind.

Dialog 2 burn one's bridges [ 関係を絶つ、背水の陣を敷く ]

Yukio:I'm quitting tomorrow, so take good care of yourself.
Angela:What?! You're quitting? I had no idea.
Yukio:Well, I haven't told anyone. I decided yesterday.
Angela:You should give the company at least two weeks notice. It's not a good idea to burn your bridges.
Yukio:Yeah, you're right. Mr. Magoo could probably help me get another job in the future.