I wouldn’t worry too much about your mother’s association with the name. As a grandpatent, I can tell you that once you see that little face, you begin falling in love with the name and the only real association is that of your grandchild.
I really disliked the name [name_m]Archie[/name_m]. [name_f]My[/name_f] grandchild was named [name_u]Archer[/name_u] and I didn’t care for the name. (His other grandmother referred to him as [name_m]Archie[/name_m] a time or two.) Within a few days, I was smitten with all things [name_u]Archer[/name_u] and [name_m]Archie[/name_m] doesn’t seem so bad now.
I agree that it should be easier to overcome with a name as popular as [name_f]Olivia[/name_f]. Perhaps your mom could refer to [name_f]Olivia[/name_f] as [name_f]Liv[/name_f] or [name_f]Livvy[/name_f] at first.