According to Michael Brickey, author of "Defying Aging," playful bantering or gentle flirting with someone outside of your marriage is harmless if proper boundaries remain intact, reports Live Science.
And he has named the 9 red flags that one should look for to know when things are getting out of hand with one’s partner:
1. If the talk has sexual agenda then you are probably in dangerous waters.
2. If you are rationalizing your relationship with the person.
3. If you are deleting your emails — either to her or from her — then that's a red flag, as deleting e-mails would mean that you are covering up something.
4. If you are sharing intimate sentiments with that person that you don’t share with your husband, or if you feel like your online companion understands you in a way that your spouse doesn't.
5. If you're spending a considerable amount of time talking to him /her than to your partner.
6. If you are sharing intimate details about your marriage or your spouse, especially in a discourteous manner or with a flip attitude.
7. You have just won a red flag if a husband or wife has expressed disapproval of your communications with someone.
8. If your friend voices concern.
9. If your intentions are wrong.