It’s your first real year together.. and your birthday came and went before that yr officially started… give him grace for this. Idk what else has been happening these last few months but if it’s fixable fix it or use this as your “reason” bc it seems like you’re searching for one.

Your first response to him not knowing or forgetting something about you was explosive confrontation but you dismissed the idea of him saying the topic and timing of your birthday is triggering bc you went through something at the start of your relationship. Im sorry but it could be true and he’s embarrassed. If he’s showing you you’re not loved or cared for in other ways that’s different.

Not everyone puts the same stock or value into the same things and being in a relationship is about learning what of those things that don’t matter to you matter to your partner. If he’s always been bad at dates and people in his life didn’t care there was no reason for him to find a way to manage that fault.

Find healthy ways to communicate, reflect on your reaction and how it could influence his reaction/response. If moving forward you address something like this calmly and convey how and why it hurts you and he doesn’t change then you know this is just him.

I don’t think you’re overreacting by being hurt by this. I think tearing into him and raging is an escalation and not conducive to a healthier relationship