When my WH left his job after D-Day, I thought I'd be ecstatic...I was to a point as OW worked for the same company, although 3,000 miles away.
What I discovered that a new set of fears set in....so, my WH gave me access to his company emails and voicemails, and I was able to see that the women (weren't many) on his team were strictly professiona. No beating around the bush, all business.
Then we moved to another state, same company, different cast of characters, and I thought, here we go again. Argh! Same situation, all professional. Nothing.
It might help if your husband is able to grant you access so you can randomly check. I STILL have access after nine years, and have only witnessed one or two emails that were gently crossing a line. WH did not respond.
My WH no longer attends any business functions when women are involved, which really helped build trust.
Your D-day is recent, and your concerns are valid. It will take a long time for you to feel safe in the marriage again, but remember, your husband's actions are key.