Bf/gf feels young, temporal, non-serious, + for me the terms are tied to stereotypical gendered expectations of behaviour and image. Husband/wife have some level of those too, but I feel they are much less present. As for why I use partner: - completely gender neutral (nb inclusive, doesn't out anyone) - feels less childish than bf/gf - reveals nothing about marital status - reveals nothing about relationship type (long-term, sexual only, polyamorous, mono)