It's not a problem that she called, it's a problem that she called, he missed it because he was doing something important to him (an activity that, let's face it, is done mostly for the purpose of getting away from everything) and you were angry at him for not checking his messages and calling back. In his mind, there was no emergency, no one was hurt, there was no need for him to call her back at that moment. He sees this from his point of view as one more example of how you hover over him and never leave him alone.
He may be right, or he may be wrong, but that's probably how he sees it. And it's a bigger problem because neither of you is probably treating this like the small incident it really was. You see it as one more in a long train of examples of him being irresponsible and out of touch. He may see it as one more in a long train of examples of you trying to control him.
But the fact that you took an incident where you lost your temper (even if you think it's justified, you lost your temper) and described it to us as an incident where he "blew up over nothing," not you, should show you that you're not seeing this clearly or objectively. You're viewing it through a lens of anger and frustration that's warping everything. And if you're that angry and frustrated, what are odds that he's not?
If you can detach and give him space, you might be shocked at how much it helps. It's completely counter-intuitive because you feel him slipping away from you and you want to grab control and pull him to you, but that's why he's fighting you in the first place. You can never force him to stay with you. Let him have room to move and see what he does.
It's so easy for me to say this and so hard for you to do it that I almost feel bad writing it . . . . but it could really make a huge difference.
