Do they discard once they lose control?

Been dealing with the fallout of my breakup with my boyfriend. It’s been 3 months, 1 month since we went no contact. I’m still struggling with feeling like it was my fault. My friend and I were planning her birthday trip when I told my boyfriend and he immediately had a problem with it. He told me if I go that we’re breaking up. I stood my ground and told him I wanted to go. Ever since then he’s just treated me like total shit. Seems very emotionless and acts as if we were never in a long term relationship. He’s definitely a narcissist, would call me names and tell me i’m unlovable and worthless. He put his hands on me once. I’ve heard about the discard phase, and I was wondering if the last straw was me going on vacation. Like was that just too much of a loss of control for him? I’m just tired of blaming myself.