In a series I've heard someone refer to wandering eye as an example of problems in a marriage.
- What kind of problems?
- He's got a wandering eye, evidently.
- So Ms. Bible Bully and I do have something in common after all.
Since the speaker, in fact, seems to have nothing in common with the mentioned woman (the bully), I'm not sure what they mean.
The best shot I have is that they refer to infidelity, as this is the most significant property of the president's marriage. However, I feel I'm missing something.