Comma before "either" at end of this sentence

Please help me determine whether or not to include a comma at the end of the third sentence:

"I won't be talking to my ex at the party tonight."

-"But what if she talks to you?"

"I won't be listening to her either."

-or-

"I won't be talking to my ex at the party tonight."

-"But what if she talks to you?"

"I won't be listening to her, either."

Thanks!