Really need advice

lizzie • 28. Mommy to a 7 year old little girl, and a 3 year old little boy. pregnant with baby #3 🤰🏼
My grandpa passed away 4 days ago, I'm 18 weeks pregnant with my daughter Reagan. My boyfriend picked out the name Reagan and we both agreed on Elizabeth for the middle name because it's my middle name too. Well now that my grandpa has passed away, I want to use his first name as her second middle name.. So I want it to be Reagan Elizabeth James, and then her last name. Well, my Ex boyfriends first name is James also... But he doesn't go by that name at all, he goes by his middle name. So I asked my boyfriend now if we could use my grandpa's name as her second middle name and he's being an absolute dick about it.. His comment was "I don't want to name our kids after any of your ex's.. And like I told him, she would be named after my grandpa... Not my ex. I get where he's coming from, but I'm also really hurt that he's being like this :(. I really need some advice or opinions 😢