At any other time and under different circumstances, it is not necessarily rude to ignore a text or email, but if you are trying to get back with your ex, ignoring your ex is a mistake that’ll come back to bite you.
Human beings in general do not forget when they’ve been treated badly. They’ll forgive and they’ll even “move past” it, but they never forget. With an ex who is emotionally guarded (afraid they may get hurt again), one who does not trust you or thinks you are into mind games, ignoring his/her text/emails just confirms what they already think of you. Not smart.
But not every text or email from your ex requires a response. The keyword here is “requires” (see texts/emails that require an immediate response) or waiting a few hours/days to reply (see texts/emails that can wait).
A response is not required/expected.
1. Contact that’s not directed to you in particular or group e-mails or forwards.
A reply may not be required/expected, but if it’s important information that your ex is sharing, e.g news about a mutual friend/family member (birth, wedding, divorce, illness, death etc), it’s polite to say, “Thanks for letting me know” or something along those lines.
2. When a topic of conversation has run it’s course and there is no more to say about it.
Trying to hang on to the conversation because you don’t want to let go of your ex comes across as needy.
3. After you have bid your goodbyes for the day or night. Not responding isn’t rude/impolite, but continuing to text long after your ex stopped responding is a little needy/clingy.
There are also times when not responding is the best response, or when responding does more damage than helps. For example:
1. Intentionally hurtful texts/emails with no purpose other than to make you feel bad.
The exception is when a ex who feels deeply hurt by something you said or did lashes out purely from the emotions of pain. Say you cheated, responding even when your ex is being intentionally hurtful is taking responsibility for your actions. It is the price you pay for your cheating.
2. Your ex contacts you then disappears, and after a few weeks contacts you again, and then… disappears AGAIN.
Not responding sends the message, “What you;re doing is not acceptable”.
3. Late night texts with no follow-up during the day/no real interest in deeper conversations.
“Scratch my itch” calls may be fluttering, but they’re not going to get the two of you back together. In fact sometimes not always, sex gets in the way of getting back together.
4. Manipulative texts/emails intended to get you to contact him/her (e.g. “I have something interesting to share/tell you” or “we need to talk” with no follow-up for hours/days).
This is obviously someone insecure looking for attention and an ego boost. You stroke their ego at your own expense.