Any marriage experience with changing last names to a completely new one? (US)

Hi everyone!

I've been trying to look up this information and it is really hard to research about this particular subject

My gf and I are in the talks of getting married & we want to change our last name to a completely new one (no hyphen, no combination) we both just dont want any association with our Family names.

We currently live in New England if that helps with States that allow this. (have previously lived in California and Washington if that also helps)

Can anyone give some advice about your experiences with this? Any information would be so helpful

Thanks!