Need advice- LONG

So me and my husband have been listing names for years now for our future baby and anytime we found one we liked we would save it.. Well we are now pregnant, expecting our first son at the end of July... We decided on our sons name back in December. After deciding on the name, my husbands aunt comes in town from NC and we announced that we are pregnant... Using my future sons name and the possible girls name. After announcing.. The aunt brings to our attention that is her daughters sons name.. (My husbands cousins sons name) & we had no idea! Small background.. His cousin lives in NC and I have literally met her once and my husband has seen her 2 times in the past 15 years! They aren't close at all.. Obviously my husband didn't even know the name of her three children.  So me and my husband tried for a month thinking of different names for my future son and never could agree on one. So me and my husband talked about it and agreed to call the cousin and ask for her blessing to use the same name. She then responds with, " I don't mind at all please use the name." March 3rd we find out it's a boy.. So now his name is set in stone. Even though his name was set in stone in December and now that I'm 24 weeks pregnant.. His cousin( that we NEVER SEE) changes her mind and wants us to change the name.. Calls us up and is a complete bitch about it honestly.. And expects us to change his name. We told her we would think about it, but my mind is already made up. His name in my heart is the name we chose in December .. Has and always will be. Not once did she ask how I felt about the situation.. it was all me me me. Granted I am pregnant but I feel like she should at least consider how it makes me feel too. Well on top of her making it a big deal, now the aunt is too .. Calling every family member trying to get them on her side. NOT ONCE DID THE COUSIN OR AUNT VOICE ANY CONCERN AND PRACTICALLY TOLD US TO NAME OUR SON IT BACK IN DEC. my husbands whole family is on our side BUT my husband wants to change his name. I'm seriously heartbroken.. I literally feel like I'm mourning his name & kinda him honestly. I know I might be over dramatic but no other name makes my heart flutter, gives me butterflies or do I feel a connection with like the name we have. 
Am I in the wrong for wanting to keep his name ?! This cousin is family yes, but literally has not seen any of our intermediate family in a really long time .. They live out of state and I don't plan on having our kids be friends or anything like that.. Our sons will be second cousins. And honestly after how she and the aunt dealt with the situation.. I could careless if I saw them again.. Ever. I'm probably being petty but this is my first pregnancy and for a month of it now i have been dealing with the stress of this.
It's keeping me up at night.. Causing fights between me and my husband.. It's just horrible. Idk what to do next..