I experienced homophobia targeted towards me for the first time from someone I love

My boyfriend of 1 year [him and I are both 18] was talking to me about judging people and said he only judges gay people but then added "straight people too." I mentioned the fact that I'm bisexual and I assumed he already knew (I've told him this before and he had no negative reaction) but he got angry with me and said "Ew ur bisexual". He then said "So you will leave me for a girl" and that his day was ruined. I explained that it doesn't mean I'm attracted to every girl and that I'm only attracted to him but he kept insisting that I will leave him for a girl. I don't plan on breaking up with him but it really hurt hearing this from my boyfriend, especially when my whole family just continued treating me normally after I came out as bisexual. I've never experienced homophobia from anyone close to me. I've known him for over 2 years now and he has never said anything bad about lgbtq so this is just really sudden.