Zita,

It’s ultimately your decision to send an email response or not. But believe me, you will be VERY VERY HAPPY that you didn’t. As seconds, minutes, hours, days, etc. go by – you constantly change your perception about everything. Time not just heals, time – helps. As you continue your journey, there will be a moment when you will laugh at your past desire to respond.
A person can only hear and comprehend his own internal voice, including your ex.
You’re going through a tough time right now, and it’s not that your mind is playing tricks on you, but your ego (identity) is just in an defensive mode, as it always is. But don’t judge it, it’s just trying to help you.
Peace to you.

Mann.