Yet, I feel triggered by this behavior and we already had a blow-up over me asking him who he's talking to. It happened last night again, where I called him around 10:30/45 and he was on the phone. I know he's not talking to his boys and based on past experience this was usually a sign of emotional cheating.

So you don't trust him.

Starting an argument out of suspicion or jealousy over who he talks to (since talking is all you know of, thus far) is indeed controlling behavior.

There is always a possibility he is seeing someone else. You can only be responsible for your own behavior, others will do what they do.

If you don't have evidence of wrongdoing, then you won't win any arguments making accusations. However, if you don't trust him, that doesn't bode well for a long term relationship.