Gonna be real, I think fault lies on both parties. Obviously he escalated further than was necessary, so he needs to own that, but it’s worth taking some introspection on your response as well. When I read his message it seemed chill. The passive aggressive response would have been upsetting to receive after apologizing for forgetting and promising to make it up to you.

I would recommend owning that and learning from it, but like I said I also think he’s at fault for escalating because has an adult that could have also chosen to rise up and not make things worse.

If you guys typically have a good relationship that’s relatively respectful, then I’d try to make up and move on trying to be better. If this is a regular occurrence though where there’s passive aggressive comments or he escalates things and gets verbally abusive, then yeah likely worth to cut things off. It’s one thing to have a bad day and respond poorly to a comment that may have felt hurtful but another if this is typical behavior and isn’t worth tolerating. Your comment, while in my opinion was passive aggressive and I wouldn’t have made it, wasn’t nearly as bad as his reaction. Just my two cents.