Whenever people report that their partner wants a divorce due to meeting someone new, the signs were there long before the relationship finally crashed. Possible clues to look out for in your wife, and one of these alone is probably not indicative but more than 3 should raise suspicions:
1. She develops a new hobby such as salsa, and you hate dancing, so she goes alone.
2. She starts going out regularly with a new female friend whom you have never met.
3. Her appearance has improved. Nicer clothes, more sexy underwear, or she has lost weight, changed her hairstyle, gone for botox, got a brace on her teeth etc.
4. She refuses to have sex with you.
5. She encourages you to work away from home or go on that golf holiday with your friends.
6. She shows no interest in you or your work.
7. She avoids you, for example 5 minutes after you walk into the sitting room she goes upstairs to have a shower. This happens a lot.
8. She has stopped arguing with you.
Of course, it may simply indicate that your wife has gone off you, but that is not good news either. Do you want to save the marriage? - suggest Relate. Do you want to end it? - hire a private investigator and see a divorce lawyer!!!!!!!!!!!!!!!!!!