Suddenly I miss him. Have I forgotten?

Three months have passed since I broke up with him. The first one was terrible, then I deeply understood and realized who he really is, I understood how much I disrespected myself by staying with him . I felt a lot of rage and all my love was gone. I was doing great, super proud of myself. I was even saying that this is the best thing that has ever happened to me, since by leaving this toxic relationship I had the opportunity to learn how to be strong and finally heal myself and love myself. Well. Suddenly all my rage disappeared and I miss him. It’s like I don’t remember why I was so angry. This emotional change happened as soon as I tried to quit smoking (I relapsed). Now I’m smoking again AND I miss him again. Is it normal that I don’t feel so strong anymore? Or so angry? He’s still behaving terribly, he’s blocked everywhere but he’s trying to have his revenge by telling people lies about myself, slut shaming me, trying to convince my boss to fire me… but I CAN’T get angry anymore. Whyyy? 😭 any advice?