You're in a tough situation because when people are suffering extreme anxiety, they can feel oversensitive to everything. If you back off and give him space, an anxious person might feel abandoned. If you show you're there, they might feel smothered. And there's no way to predict what the reaction will be because it's often coming from inside the other person's own insecurities instead of being a rational response to your action.

So ... what do you want to do? Back off all the way? Or let him know you're there?

One of my best friends has panic attacks and general anxiety. When he's in an anxious state, it doesn't matter what I do, it's wrong. He later apologizes, but while he's anxious, everything rubs him the wrong way.

I can tell you the thing he responds to best is something like a text that says only, "Hey." Or "Hi." Then he decides whether and how too respond.

Because nothing I can do in the moment is going to be interpreted as right, I choose to do the thing that is the least disruptive or distressing to me. That usually means giving us both space. When he's all bristled up and feeling defensive about everything, I need my space away from him until he calms down.

I don't know what your BF is experiencing, but it might be beneficial to you to be prepared that no matter what you do, you can't predict how he'll respond. But maybe just a texted "Hey" or "Wsup" or whatever the two of you might ordinarily say if things were okay, just to touch bases, might be okay. His response will probably depend on how he feels in the exact moment that he reads the text. Unpredictable as hell!

Good luck to you.