This was DH but with the texting and calls. Though anything I ever overhead or saw was always business related. They are 2 high profile figures with jobs that go 24/7. To this day though, my gut still tells me something may have been going on though.

If you feel uncomfortable, be honest with your DH. However, if he's trustworthy, there's nothing to fear. I know it's not easy, but give him (and her) the benefit of the doubt.