Baby name/ babys dad left/ short rant

He chose her name, Abigail. I grew to like it but I really liked Mila. So "we" agreed on Abigail Mila.. Well he up and left because "he just doesn't love me anymore". So I changed the baby's name to Mila Abigail. He still gets his Abigail in there as well as his last name. But he is SO MAD that I decided to name her Mila instead of Abigail.  Like... Doesn't he lose the right to name the baby when he straight up walked out on myself and my other 2 kids that he's raised? How do I know he won't walk out of Milas life too? My other kids' father did and I 100% regret letting him choose the name of our first child together. Plus.. My other two are Kaislee and Khaleb(pronounced kaleb) ... Thanks ex husband. I think Mila just fits in better than Abigail. Kaislee is so unique and Khalebs spelling is unique too.  In pretty sure Abigail is like in the top 5-10 baby names of 2016....