Lol this could actually work...
In fact, I'd be surprised if it hasn't already been done. A general intelligent auto-reply bot that runs each received message alongside a summary of the relationship situation, and sends back the generated reply. Or perhaps offers a list of possible replies to choose from.
Could cover multiple channels: text, email, messenger, whatsapp
Clearly something similar is already present on Twitter against Trump etc.
I've noticed that for the past few months, every time I tweet, I get one random different account like the tweet moments later, so they're obviously not real people.